Jesus Christ says to the Church at Pergamos:
"But I have a few things against thee, because thou hast there them that hold the doctrine of Balaam, who taught Balac to cast a stumblingblock before the children of Israel, to eat things sacrificed unto idols, and to commit fornication." Revelation 2:14


The people of Israel began to adopt the pagan customs that were around them and God no longer blessed them.