One passage from gMatthew defines the best most of the main beliefs of Jewish Christians:
25:31But when the Son of man shall come in his glory, and all the angels with him, then shall he sit on the throne of his glory: 25:32and before him shall be gathered all the nations: and he shall separate them one from another, as the shepherd separateth the sheep from the goats; 25:33and he shall set the sheep on his right hand, but the goats on the left. 25:34Then shall the King say unto them on his right hand, Come, ye blessed of my Father, inherit the kingdom prepared for you from the foundation of the world: 25:35for I was hungry, and ye gave me to eat; I was thirsty, and ye gave me drink; I was a stranger, and ye took me in; 25:36naked, and ye clothed me; I was sick, and ye visited me; I was in prison, and ye came unto me. 25:37Then shall the righteous answer him, saying, Lord, when saw we thee hungry, and fed thee? or athirst, and gave thee drink? 25:38And when saw we thee a stranger, and took thee in? or naked, and clothed thee? 25:39And when saw we thee sick, or in prison, and came unto thee? 25:40And the King shall answer and say unto them, Verily I say unto you, Inasmuch as ye did it unto one of these my brethren, even these least, ye did it unto me. 25:41Then shall he say also unto them on the left hand, Depart from me, ye cursed, into the eternal fire which is prepared for the devil and his angels: ...
Added to that, Jesus is not pre-existent in the gospel, but starts his life by his birth from Mary. Also the Kingdom of God to come is to be extended from heaven to earth:
6:10Thy kingdom come. Thy will be done, as in heaven, so on earth.
And obeying and practicing the whole of the Law is essential:
5:18For verily I say unto you, Till heaven and earth pass away, one jot or one tittle shall in no wise pass away from the law, till all things be accomplished. 5:19Whosoever therefore shall break one of these least commandments, and shall teach men so, shall be called least in the kingdom of heaven: but whosoever shall do and teach them, he shall be called great in the kingdom of heaven.
Cordially, Bernard