The first thing I notice with reguards to how a Born Again Believer, someone who has felt the move of the Holy Spirit, can leave their Messiah, is isolation.
Hebrews 10: 23Let us continue holding fast to the hope we acknowledge, without wavering; for the One who made the promise is trustworthy. 24 And let us keep paying attention to one another, in order to spur each other on to love and good deeds, 25 not neglecting our own congregational meetings, as some have made a practice of doing, but, rather, encouraging each other. And let us do this all the more as you see the Day approaching.
Paying attention to one another, encouraging one another, not neglecting meetings of Believers all of these are linked in the Author’s mind to holding fast the promise that Yeshua made, that of Salvation and his return.
What happens when a group isolates themselves?…kool-aid and those guys in the jumpsuits that were going to meet the mother ship come to mind. What I’m saying here is if you isolate yourself, neglect the fellowship of the Believers, then you will follow that path to a bad conclusion. In matters of the Spirit you will follow a path that leads to wavering, losing hope and eventually rejecting the Messiah.
Let’s say you are a Mainstream Christian you keep Christmas, Easter go to church on Sunday. I am not I keep Sukkot, and Rosh Hashana and go to services on Sabbath. We both believe that Yeshua, Jesus, is the Messiah and our Savior, we both believe in a Virgin Birth, Crucifixion and Resurrection. Why then can’t we both attend a Bible Study together? Why then can’t we sit at the Shabbat table though I choose to dress modest and you don’t? Why is it that we will say well they aren’t doing it right, so we leave the Church, move to the home study and then finally refuse to study with anyone cause they don’t do it right either and then…we have found ourselves rejecting Yeshua and there wasn’t anyone there to say hey I’m not sure about that text, or maybe there is Scripture about that or…you see?
So this is my first answer to how does someone leave Yeshua….Isolation, self imposed, through fear or pride of those who Believe but live it out differently.