The warning against a latter-day apostasy in these texts involves a number of heresies--following devils, forbidding to marry, and commanding to abstain from certain foods.
Perhaps the greatest misunderstanding has arisen over verse 4, where it is stated that "every creature of God is good." This means that every created thing has been made for a need and a purpose. But some suppose that every animal is therefore good to be eaten if it is properly prayed over and blessed by the prayer of thanksgiving. Not so! Praying over a buzzard or mole or bat will not make it fit for food. Then, in case anyone should come to wrong conclusions from verse 4, Paul hastens to add: "For it is sanctified by the word of God and prayer." Verse 5. Ah, now we know what sanctifies it as proper for the diet. The Word of God must approve it, and then the prayer of thanksgiving will sanctify it to be eaten.
It is helpful to note that the word "meats" in the original language is not limited to flesh foods. The Greek word "broma" simply means "food." Notice also that this discussion does not involve biblically unclean animals. Those meats which some had forbidden were meats "which God hath created to be received with thanksgiving of them which believe and know the truth." Verse 3. Now it is easy to find in the Bible God's description of the meats which He created to be received with thanksgiving (Leviticus 11:2-20). Those who "believe and know the truth" will receive those foods with thanksgiving because they are "sanctified by the word of God and prayer." God' s Word is the truth. Only those who "believe and know" that Word will be led to those things that are "sanctified" and created to "be received with thanksgiving.'' Those who "sanctify themselves" while eating unclean meats wall be destroyed at Christ second coming (see Isaiah 66:15-17).