Adam Clarke on 1 Timothy 4:3

Forbidding to marry - These hypocritical priests pretending that a single life was much more favorable to devotion, and to the perfection of the Christian life. This sentiment was held by the Essenes, a religious sect among the Jews; and we know that it is a favourite opinion among the Romanists, who oblige all their clergy to live a single life by a vow of continency.

To abstain from meats - Both among the heathens, Jews, and Romanists, certain meats were prohibited; Some always, others at particular times. This the apostle informs us was directly contrary to the original design of God; and says that those who know the truth, know this.