How sadistic is the god of the bible?

I m always astounded by God's mercy in the Old Testament because Israel kept leaving Him to follow the baby-burning combined with m ual orgies religions around them when He had been so good to them. If people do not want Him He will finally leave them to the evil humans around them who take pleasure in evil (e.g. smashing babies, etc.) Or He will leave them to their Godless selves resuling in eating their own babies etc.