This difference of vocabulary can be seen most vividly in the account of Jesus calming the storm:
Mark 4.35-41: 35 On that day, when evening came, He says to them, “Let us go over to the other side.” 36 Leaving the crowd, they take Him along with them in the boat, just as He was; and other boats were with Him. 37 And there arises a fierce gale of wind, and the waves were breaking over the boat so much that the boat was already filling up. 38 Jesus Himself was in the stern, asleep on the cushion; and they wake Him and say to Him, “Teacher, do You not care that we are perishing?” 39 And He got up and rebuked the wind and said to the sea [θαλάσσῃ], “Hush, be still.” And the wind died down and it became perfectly calm. 40 And He said to them, “Why are you afraid? Do you still have no faith?” 41 They became very much afraid and said to one another, “Who then is this, that even the wind and the sea [θάλασσα] obey Him?” | Luke 8.22-25: 22 Now on one of those days Jesus and His disciples got into a boat, and He said to them, “Let us go over to the other side of the lake [λίμνης].” So they launched out. 23 But as they were sailing along He fell asleep; and a fierce gale of wind descended on the lake [λίμνην], and they began to be swamped and to be in danger. 24 They came to Jesus and woke Him up, saying, “Master, Master, we are perishing!” And He got up and rebuked the wind and the surging waves [κλύδωνι τοῦ ὕδατος], and they stopped, and it became calm. 25 And He said to them, “Where is your faith?” They were fearful and amazed, saying to one another, “Who then is this, that He commands even the winds and the water [ὕδατι], and they obey Him?” |
However, Marcion is attested as mentioning the sea here. Tertullian attests (the standard Latin translation of) this word at Against Marcion 4.20.1: "Who then is this man who commands both the winds and the sea [mari]?" This attestation is all the more meaningful since Tertullian immediately turns around and, in his own words, describes in the same context the bodies of water in Palestine as "the lakes" or "pools of Judea" (stagna Iudaeae). Epiphanius also attests "sea" instead of "lake" for the Marcionite gospel in Panarion 42.11.6: "As they sailed he fell asleep. Then he arose and rebuked the wind and the sea [θαλάσσῃ]."
If Marcion simply truncated the gospel of Luke, then we have on our hands an interesting sequence (on most theories of synoptic interrelations) whereby Mark wrote (inaccurately) of the sea, Luke changed this (more accurately) to a lake with waves of water, and then Marcion (inaccurately) changed it back again to the sea. Why would Marcion do this? Does it not make a bit more sense to suppose that the texts which speak of the sea preceded canonical Luke, which changed it to a lake, possibly so as to avoid criticisms such as those later leveled against the gospels by the likes of Porphyry?
Ben.