I've been musing that it might have been a transcription of תשיש = weak, feeble. The question for me has always been:
1. if there was an original gospel written in Hebrew or Aramaic
2. and if the Greek gospel took over divine names at the start of the process toward nomina sacra
what was the original Hebrew terminology behind XCIC? I've mused before about 'man' = eesh being behind IC. What I find even more interesting is the awkwardness of XCIC. How could Tertullian for instance say that 'Christ Jesus' descended from heaven given that he hadn't been anointed at the start of the gospel? You'd have to suspect that one was the Christ only after being anointed (and for that matter it has always struck me as odd that Jesus was ever identified as 'anointed one' when anointing and enthronement does not figure prominently in the gospel as one would suspect if it were a messianic document).
But if - let's say - there was an original Aramaic text and Paul especially made frequent terminology to the masculine noun תשיש = weak (one), feeble (one). The tau might well have looked like a chi on the page
The idea of the Marcionites say that the Creator was weak, feeble, less than perfect is well attested. However I don't think it is well understood as an attested position within Judaism. Let's look at the most explicit statement about Marcion's attitude toward Moses and Yahweh:
So he swears by himself, so that you may believe God, at least on his own oath, that there is no other god at all. And it is you, Marcion, who have forced God to do this: for even so long ago God had foreknowledge of you. Consequently if in his promises, and in his threatenings besides, God uses an oath in dragging forth that faith which in its beginnings is hard to attain to, there is nothing unworthy of God in that which causes men to believe in God. On that other occasion also God made himself little even in the midst of his fierce anger, when in his wrath against the people because of the consecration of the (golden) calf he demanded of his servant Moses, Let me alone, and I will wax hot in wrath and destroy them, and I will make thee into a great nation. On this you are in the habit of insisting that Moses was a better person than his own God—deprecating, yes and even forbidding, his wrath: for he says, Thou shalt not do this: or else destroy me along with them. Greatly to be pitied are you, as well as the Israelites, for not realizing that in the person of Moses there is a prefiguring of Christ, who intercedes with the Father, and offers his own soul for the saving of the people. But for the present it is enough that the people were granted even to Moses in his own person. Also, so that the servant might be in a position to make this request of his Lord, the Lord made that request of himself. That is why he said to his servant, Let me alone and I will destroy them, so that the servant might forestall this by his prayer and his offering of himself, and so that you by this might learn how much is permitted to one who has faith, and is a prophet, in the presence of God. [Adv Marc 2.26]
Exodus 32:10 is a well known objection against Yahweh being the Almighty God. In Berakoth 32 we read:
ואמר רבי אלעזר משה הטיח דברים כלפי מעלה שנאמר (במדבר יא, ב) ויתפלל משה אל ה' אל תקרי אל ה' אלא על ה'
And Rabbi Elazar said: Moses also spoke impertinently toward God on High, as it is stated: “And Moses prayed to the Lord (and the fire subsided)” (Numbers 11:2), Do not read to [el] the Lord, but rather onto [al] the Lord, (which indicates that he spoke impertinently).
שכן דבי רבי אליעזר בן יעקב קורין לאלפין עיינין ולעיינין אלפין
As the school of Rabbi Eliezer ben Ya’akov would read alef as ayin and ayin as alef (and in this case transforming el into al).
דבי רבי ינאי אמרי מהכא (דברים א, א) ודי זהב
The school of Rabbi Yannai, say (proof that Moses spoke impertinently toward God on High is derived) from here (Moses’ rebuke at the beginning of Deuteronomy): “And Di Zahav” (Deuteronomy 1:1). (This is an entry in a list of places where Moses had spoken to Israel. As there was no place encountered by that name, it is interpreted as an allusion to another matter).
מאי ודי זהב אמרי דבי ר' ינאי כך אמר משה לפני הקב"ה רבונו של עולם בשביל כסף וזהב שהשפעת להם לישראל עד שאמרו די הוא גרם שעשו את העגל
What is (the meaning of and) Di Zahav? The school of Rabbi Yannai said that Moses said the following before the Holy One, Blessed be He, (to atone for Israel after the sin of the Golden Calf): Master of the Universe, because of the gold and silver that you lavished upon Israel (during the exodus from Egypt) until they said enough [dai]; (it was this wealth) that caused (Israel) to make the Golden Calf.
אמרי דבי ר' ינאי אין ארי נוהם מתוך קופה של תבן אלא מתוך קופה של בשר
(Establishing a general moral principle, the Sages) the school of Rabbi Yannai said: A lion does not roar (standing) over a basket of straw ()from which he derives no pleasure), but (he roars) standing over a basket of meat, (as he only roars when satiated).
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(שמות לב, ז) וידבר ה' אל משה לך רד מאי לך רד אמר רבי אלעזר אמר לו הקדוש ב"ה למשה משה רד מגדולתך כלום נתתי לך גדולה אלא בשביל ישראל ועכשיו ישראל חטאו אתה למה לי מיד תשש כחו של משה ולא היה לו כח לדבר וכיון שאמר (דברים ט, יד) הרף ממני ואשמידם אמר משה דבר זה תלוי בי מיד עמד ונתחזק בתפלה ובקש רחמים
(The Gemara elaborates upon additional aspects of the sin of the Golden Calf. It is stated:) “And the Lord said to Moses: Go and descend, (for your people whom you have lifted out of the land of Egypt have been corrupted”) (Exodus 32:7). What is (the meaning of) “go and descend”? Rabbi Elazar said: The Holy One, Blessed be He, said to Moses: Moses, descend from your greatness. Isn’t it only for the sake of Israel, (so that you may serve as an emissary), that I granted you prominence; and now that Israel has sinned, why do I (need) you? (There is no need for an emissary). Immediately, Moses’ strength waned and he was powerless to speak (in defense of Israel). And once (God) said (to Moses): “Leave Me be, that I may destroy them” (Deuteronomy 9:19), Moses said (to himself: If God is telling me to let Him be, it must be because) this matter is dependent upon me. Immediately Moses stood and was strengthened in prayer, and asked (that God have) mercy (on the nation of Israel and forgive them for their transgression).
...
(שמות לב, י) ועתה הניחה לי ויחר אפי בהם ואכלם ואעשה אותך לגוי גדול וגו' אמר רבי אבהו אלמלא מקרא כתוב אי אפשר לאומרו מלמד שתפסו משה להקדוש ברוך הוא כאדם שהוא תופס את חבירו בבגדו ואמר לפניו רבונו של עולם אין אני מניחך עד שתמחול ותסלח להם:
(In an additional aspect of the sin of the Golden Calf, God told Moses:) “Now leave Me be, that My wrath will be enraged against them and I will consume them; and I will make of you a great nation” (Exodus 32:10). (Explaining this verse), Rabbi Abbahu said: Were the verse not written (in this manner) it would be impossible to utter it, (in deference to God. The phrase: Leave Me be), teaches that Moses grabbed the Holy One, Blessed be He, as a person who grabs his friend by his garment (would), and he said before Him: Master of the Universe, I will not leave You be until You forgive and pardon them.
(שמות לב, י) ואעשה אותך לגוי גדול וגו' אמר רבי אלעזר אמר משה לפני הקדוש ב"ה רבונו של עולם ומה כסא של שלש רגלים אינו יכול לעמוד לפניך בשעת כעסך כסא של רגל אחד על אחת כמה וכמה
In the same verse, God promised Moses: “And I will make of you a great nation.” What was Moses’ response? Rabbi Elazar said: Moses said before the Holy One, Blessed be He: Master of the Universe, if a chair with three legs, the collective merit of the three forefathers, is unable to stand before You in Your moment of wrath, all the more so that a chair with one leg, my merit alone, will be unable to withstand your wrath.
ולא עוד אלא שיש בי בושת פנים מאבותי עכשיו יאמרו ראו פרנס שהעמיד עליהם בקש גדולה לעצמו ולא בקש עליהם רחמים:
Moreover, but I have a sense of shame before my forefathers. Now they will say: See this leader that God placed over Israel. He requested greatness for himself but did not pray for God to have mercy upon them in their troubled time.
(שמות לב, יא) ויחל משה את פני ה' אמר רבי אלעזר מלמד שעמד משה בתפלה לפני הקדוש ברוך הוא עד שהחלהו ורבא אמר עד שהפר לו נדרו כתיב הכא ויחל וכתיב התם (במדבר ל, ג) לא יחל דברו ואמר מר הוא אינו מיחל אבל אחרים מחלין לו
The Torah continues: “And Moses beseeched [vayḥal] before the Lord” (Exodus 32:11). Many interpretations were given for this uncommon term, vayḥal: Rabbi Elazar said: It teaches that Moses stood in prayer before the Holy One, Blessed be He, until it made him ill [heḥelahu] from overexertion. And Rava said: Moses stood in prayer until he nullified His vow, as the term vayḥal alludes to nullification of an oath. Here it is written vayḥal, and there referring to vows, it is written: “He shall not nullify [lo yaḥel] his word” (Numbers 30:3). And with regard to vows, the Master said: He who vowed cannot nullify his vow, but others, the court, can nullify his vow for him. Here, it is as if Moses nullified the Lord’s vow to destroy Israel.
ושמואל אמר מלמד שמסר עצמו למיתה עליהם שנאמר (שמות לב, לב) ואם אין מחני נא מספרך
And Shmuel said: The term vayḥal teaches that Moses gave his life, from the term ḥalal, a dead person, for Israel, as it is stated: “And if not, erase me, please, from Your book” (Exodus 32:32).
אמר רבא אמר רב יצחק מלמד שהחלה עליהם מדת רחמים
Rava, also interpreting this verse, said that Rav Yitzḥak said: The term vayḥal teaches that he caused the Divine Attribute of Mercy to take effect [heḥela] upon them.
ורבנן אמרי מלמד שאמר משה לפני הקב"ה רבש"ע חולין הוא לך מעשות כדבר הזה
And the Rabbis say that this term constitutes the essence of Moses’ claim: It teaches that Moses said before the Holy One Blessed be He: It is a sacrilege [ḥullin] for You to do something like this.
ויחל משה את פני ה' תניא רבי אליעזר הגדול אומר מלמד שעמד משה בתפלה לפני הקדוש ברוך הוא עד שאחזתו אחילו מאי אחילו אמר רבי אלעזר אש של עצמות מאי אש של עצמות אמר אביי אשתא דגרמי
And another interpretation of the verse, “And Moses beseeched [vayḥal] before the Lord.” It was taught in a baraita: Rabbi Eliezer the Great says: This term teaches that Moses stood in prayer until he was overcome by aḥilu. Even the Sages were unfamiliar with this term. Therefore, the Gemara asks: What is the meaning of aḥilu? Rabbi Elazar, an amora of Eretz Yisrael, said that aḥilu is fire in the bones. However, this expression was familiar in Eretz Yisrael but not in Babylonia. They asked in Babylonia: What is the disease that they called fire of the bones? Abaye said that is a disease known in Babylonia as eshta degarmei, which in Aramaic means fire of the bones; in other words, a fever.
(שמות לב, יג) זכור לאברהם ליצחק ולישראל עבדיך אשר נשבעת להם בך מאי בך אמר רבי אלעזר אמר משה לפני הקדוש ב"ה רבונו של עולם אלמלא נשבעת להם בשמים ובארץ הייתי אומר כשם ששמים וארץ בטלים כך שבועתך בטלה ועכשיו שנשבעת להם בשמך הגדול מה שמך הגדול חי וקיים לעולם ולעולמי עולמים כך שבועתך קיימת לעולם ולעולמי עולמים:
As Moses continues his prayer, he says: “Remember Abraham, Isaac and Israel Your servants, to whom You swore in Your name” (Exodus 32:13). What is the meaning of in Your name? Rabbi Elazar said: Moses said before the Holy One, Blessed be He: Master of the Universe, had You sworn to them by the heavens and the earth, I would say: Just as the heavens and the earth will ultimately be no more, so too Your oath will be null and void. Now that You swore to them by Your great name, just as Your name lives and stands for all eternity, so too does Your oath live and stand for all eternity.
(שמות לב, יג) ותדבר אליהם ארבה את זרעכם ככוכבי השמים וכל הארץ הזאת אשר אמרתי האי אשר אמרתי אשר אמרת מיבעי ליה
In this verse, Moses continues: “And You said to them: I will make your offspring as numerous as the stars of heaven, and all this land of which I have spoken I will give to your offspring that they shall inherit it forever.” The Gemara clarifies a puzzling phrase in this verse. That phrase of which I have spoken, it should have said: Of which You have spoken, as Moses is referring to God’s promise to the forefathers.
אמר רבי אלעזר עד כאן דברי תלמיד מכאן ואילך דברי הרב ורבי שמואל בר נחמני אמר אלו ואלו דברי תלמיד אלא כך אמר משה לפני הקדוש ברוך הוא רבונו של עולם דברים שאמרת לי לך אמור להם לישראל בשמי הלכתי ואמרתי להם בשמך עכשיו מה אני אומר להם:
Rabbi Elazar said: To this point, the verse cites the words of the student, Moses; from this point, and all this land of which I have spoken, the verse cites the words of the Master, God. And Rabbi Shmuel bar Naḥmani said: These and those are the words of the student; Moses spoke the entire verse. Rather, Moses said before the Holy One, Blessed be He: Master of the Universe, those matters which You told me to go and say to Israel in My name, I went and told it to them in Your name. I have already told Israel of God’s promise to the forefathers. Now what do I say to them?
(במדבר יד, טז) מבלתי יכולת ה' יכול ה' מיבעי ליה
The Gemara moves to a discussion of additional prayers offered by Moses. Moses said that if God fails to bring the Jewish people into Eretz Yisrael, the nations of the world will say: “The Lord did not have the ability [yekholet] to bring this people into the land which He swore to them, and He killed them in the desert” (Numbers 14:16). The Gemara examines this verse closely: The verse should not have utilized the term yekholet, an abstract feminine noun, but rather, it should have said: “The Lord was not able [yakhol],” a masculine verb.
אמר רבי אלעזר אמר משה לפני הקב"ה רבש"ע עכשיו יאמרו אומות העולם תשש כחו כנקבה ואינו יכול להציל אמר הקב"ה למשה והלא כבר ראו נסים וגבורות שעשיתי להם על הים אמר לפניו רבונו של עולם עדיין יש להם לומר למלך אחד יכול לעמוד לשלשים ואחד מלכים אינו יכול לעמוד
Rabbi Elazar said: Moses phrased it that way because he said before the Holy One, Blessed be He: Master of the Universe, now the nations of the world will say that His strength weakened like a female and He is unable to rescue the nation of Israel. The Holy One, Blessed be He, said to Moses: And did the nations of the world not already see the miracles and the mighty acts that I performed on behalf of Israel at the Red Sea? Moses said before Him: Master of the Universe, they can still say: The Lord can stand up to a single king like Pharaoh and defeat him, but He is unable stand up to the thirty-one kings in the land of Canaan.
אמר ר' יוחנן מנין שחזר הקדוש ברוך הוא והודה לו למשה שנאמר (במדבר יד, כ) ויאמר ה' סלחתי כדברך תני דבי רבי ישמעאל כדבריך עתידים אוה"ע לומר כן
Rabbi Yoḥanan said: From where is it derived that the Holy One, Blessed be He, ultimately conceded to Moses? As it is said: “And the Lord said: I have forgiven according to your word” (Numbers 14:20). The Sages of the school of Rabbi Yishmael taught: According to your word, it will be, as indeed in the future the nations of the world will say this.
אשרי תלמיד שרבו מודה לו
The Gemara concludes: Happy is the student whose teacher concedes to him as the Lord conceded to Moses.
(במדבר יד, כא) ואולם חי אני אמר רבא אמר רב יצחק מלמד שאמר לו הקדוש ב"ה למשה משה החייתני בדבריך:
Explaining the next verse, “Nevertheless, as I live, and the glory of the Lord fills the entire world” (Numbers 14:21), Rava said that Rav Yitzḥak said: This teaches that the Holy One, Blessed be He, said to Moses: Moses, you have given Me life with your words. I am happy that on account of your arguments, I will forgive Israel.
דרש רבי שמלאי לעולם יסדר אדם שבחו של הקב"ה ואחר כך יתפלל מנלן ממשה דכתיב (דברים ג, כג) ואתחנן אל ה' בעת ההיא וכתיב ה' אלהים אתה החלות להראות את עבדך את גדלך ואת ידך החזקה אשר מי אל בשמים ובארץ אשר יעשה כמעשיך וכגבורותיך וכתיב בתריה אעברה נא ואראה את הארץ הטובה וגו':
Based on Moses’ prayers, Rabbi Simlai taught: One should always set forth praise of the Holy One, Blessed be He, and then pray for his own needs. From where do we derive that one should conduct himself in this manner? From Moses, as it is written in his prayer: “And I beseeched the Lord at that time” (Deuteronomy 3:23). And immediately afterward in his prayer, it is written: “Lord, God, You have begun to show Your servant Your greatness and Your strong hand, for what God is there in the heavens or on earth who can perform deeds such as Yours and Your might” (Deuteronomy 3:24)? Here, Moses began with praise of God, and it is only thereafter that it is written: “Please, let me pass over and see the good land that is beyond the Jordan, that good hill country and the Lebanon” (Deuteronomy 3:25). Only after his praise did Moses make his personal request.
(סימן מעשי"ם צדק"ה קרב"ן כה"ן תעני"ת מנע"ל ברז"ל):
The Gemara prefaces the next discourse with a mnemonic symbol: Deeds, charity, offering, priest, fast, shoe, iron.
I will explain this at more length but clearly all Marcion's position related to the Golden Calf incident from multiple sources are attested in this tractate. Marcionism is therefore an attested Jewish - most clearly associated with the school of Yannai. I think it highly probable they called the second god 'the weak one.' But have to go to work right now ...
“Finally, from so little sleeping and so much reading, his brain dried up and he went completely out of his mind.”
― Miguel de Cervantes Saavedra, Don Quixote