Neither be ye idolaters, as were some of them; as it is written, The people sat down to eat and drink, and rose up to play.
Idolaters. A case in point. As the Israelites sat down (a deliberate act), ate, and drank at the idol feast to the calves in Horeb, so the Corinthians were in danger of idolatry by a like act, though not professedly worshipping an idol, as the Israelites (Exodus 32:6; 1 Corinthians 8:10-11; 1 Corinthians 10:14; 1 Corinthians 10:20-21). He passes from the first to the second person, as they alone (not he also) were in danger of idolatry. He resumes the first person appropriately at 1 Corinthians 10:16.
Some. The multitude follow the lead of some bad men.
Play - with lascivious dancing, singing, and drumming round the calf (cf. "rejoiced," Acts 7:41).