And falling to the ground, he heard a voice saying to him, “Saul, Saul, why are you persecuting me?”
Acts 9:4

Persecuting Yeshua's people is the same as persecuting Yeshua himself. There's no indication that the Christians in Syria were especially righteous. They were people just like any other--flawed and sinful--yet Yeshua still called them "me".

Be careful whom you persecute.