……which has been occurring since that Revelation was given, and it will continue until Christ's return.
They were worshiping Satan, in Moloch. Devils' doctrines are presented as doctrines from heaven. Moloch worshipers, as with all false gods, thought they were worshiping a good god, not Satan. Since they believed their god was good, so therefore did they believe the sacrifices they did for it were also holy and good.