https://www.google.com/books/edition/Re ... 1249193192
But there are some things that come to mind when I think about the idea that the Ebionites emerged after 70 CE. For one, while Paul and the Letter of James (which I view as being genuine and thus pre-70 CE) champion the poor, neither (to my knowledge) use the word "ebionite" to describe Jesus or his followers. As Paul says in Gal. 2:10 and Rom. 15:26 (for examples):
All they [Jewish Christian leaders] asked was that we should continue to remember the poor [ptochon], the very thing I had been eager to do all along.
For Macedonia and Achaia were pleased to make a contribution for the poor [ptochous] among the Lord's people in Jerusalem.
And James uses the same word several times in chapter 2, e.g., 2:5:
Has not God chosen the poor [ptochous] of this world to be rich in faith and to inherit the kingdom He promised those who love Him?
And Jesus uses the same word in Mark and Matthew (which I view as being the earliest gospels) and in the other NT gospels, e.g., Mt. 5:3:
Blessed are the poor [ptochoi] in spirit, for theirs is the kingdom of heaven.
https://biblehub.com/greek/4434.htm
Does the New Testament use the word "ebionite" at all? If so, I haven't been able to find it yet. And in any event it at least wasn't used in the above contexts to describe the followers of Jesus. But I do know that some of these sources and others I view as being from the first century CE (i.e., Luke and Acts, which I suspect were written c. 95 CE) use the word "Nazarene" (whatever it may mean) to describe Jesus' followers and Jesus himself. For examples:
Mk. 1:24:
What do we have to do with you, Jesus, Nazarene?
Mk. 10:47:
When he heard that it was Jesus the Nazarene, he began to cry out and say, "Jesus, Son of David, have mercy on me!"
Mk. 14:67:
When she saw Peter warming himself, she looked closely at him. "You also were with that Nazarene, Jesus," she said.
Mt. 2:23:
And he went and lived in a city called Nazareth, so that what was spoken by the prophets might be fulfilled, that he would be called a Nazarene.
Acts 24:5:
We have found this man [Paul] to be a troublemaker, stirring up riots among the Jews all over the world. He is a ringleader of the Nazarene sect ...
So I'm thinking that if the earliest sources we have (which I view as being from the first century CE, though after 70 CE in the case of Mark, Matthew, Luke and Acts) use the word "Nazarene" to describe Jesus and his followers and don't use the word "ebionite" (or if they do, then not exclusively or as a title of a sect like in Acts 24:5), then this would support what Epiphanius says about the Ebionite faction of Jewish Christianity emerging from the Nazarene faction sometime after 70 CE.