Read I Kings 12:20-33
5. A new festival.
Jeroboam instituted his own festival a month after the Feast of Tabernacles, the pre-eminent feast of the southern kingdom in Jerusalem. His was a month later on the 15th day of the eighth month. c.f. Lev.23 and Numb. 29:12-38. Why mimic this feast? Probably because it was one of the longer (8 days), a feast of joy and harvest (Deut.16:14 and Lev.23:40) and it was the feast with the most offerings. What does Hosea have to say about it–see chapter 2:11 and 9:1-2. Amos likewise also condemned in no uncertain terms this man-made worship (see 5:21ff and 8:10). This ought to be a lesson to all who bring in man-made doctrine and worship practice to God’s church today. The Regulative Principle of worship followed by true Reformed churches stipulates that only what God commands should be part of public worship.