Because of their sins, whereby they provoked him to anger. Or, by reason of his great and just anger against them he abhorred, or reprobated, or cast off his sons and his daughters, for such they were by calling and profession, but not in truth and reality, Deuteronomy 32:5.
Related Commentaries of Deuteronomy 32:19
Deuteronomy 32:19
19 And when the LORD saw it, he abhorredc them, because of the provoking of his sons, and of his daughters.