(Caesarea. Circa 279-320 CE, student of Rabbi Yohanan)
The early 4th century saw the ascendancy of Christianity as the dominant religious force in the Roman Empire. The first Christian emperor, Constantine (he was taught the religion by his mother, Helena), removed all penalties for professing Christianity in 313. His Council of Nicaea in 325 distanced the observance of Easter from Pesach:
"... it appeared an unworthy thing that in the celebration of this most holy feast we should follow the practice of the Jews, who have impiously defiled their hands with enormous sin, and are, therefore, deservedly afflicted with blindness of soul. ... Let us then have nothing in common with the detestable Jewish crowd; for we have received from our Saviour a different way."
- Eusebius, Life of Constantine Vol. III Ch. XVII (Caesarea, 263-339 CE)
"It was, in the first place, declared improper to follow the custom of the Jews in the celebration of this holy festival, because, their hands having been stained with crime, the minds of these wretched men are necessarily blinded. ... Let us, then, have nothing in common with the Jews, who are our adversaries. ... Let us ... studiously avoiding all contact with that evil way. ... For how can they entertain right views on any point who, after having compassed the death of the Lord, being out of their minds, are guided not by sound reason, but by an unrestrained passion, wherever their innate madness carries them. ... lest your pure minds should appear to share in the customs of a people so utterly depraved. ... Therefore, this irregularity must be corrected, in order that we may no more have any thing in common with those parricides and the murderers of our Lord. ... no single point in common with the perjury of the Jews.
In 329, Constantine prohibited Jews from circumcising their salves and from owning Christian slaves. The death penalty was imposed against those found guilty of having converted to Judaism and on Jews found guilty of having married a Christian. The long era of state sanctioned hostility to the Jewish people had begun.