Only grace believers have “the faith,” so only they can “depart” from it (v.1). In the last days one of the “doctrines of devils” they’ll teach is “forbidding to marry” (v.3). Devils will want grace leaders teaching this in the last days to limit the number of grace believers through children right before the Rapture to limit the amount of accurate grace literature we’ll leave behind. Most Christian literature doesn’t even know that faith plus works should be preached in the Tribulation.
Satan is always working ahead to oppose what God plans to do. When God announced the Savior would be the seed of the woman, he worked ahead of His birth to pollute her seed with seducing spirits (Gen.6:1,2), then again with Noah’s new race (Gen.6:4). Satan directed the new crop of giants to the promised land when he heard God send Abram there (Gen. 12:1) to be there to oppose God when he got there (v.6).
That’s what Satan will do in the last days, get seducing spirits to work ahead to pollute accurate Tribulation literature that will be left behind at the rapture. But why will grace leaders forbid the institution that usually generates more church members through children? Men who are “seduced” do many things contrary to their own best interests. What men find seductive varies, but grace believers find Pauline doctrine seductive, and Paul discouraged marriage (ICor.7:27) because he thought he’d live to see the Rapture and so he thought the “distress” he was going through (v.26) was the last days. It doesn’t make sense to have babies in times of distress (cf.Lu.21:23). So to be like Paul, grace believers will forbid to marry when the last days finally do arrive
This shows Paul hadn’t yet learned our last days won’t be distressed with persecution like Israel’s will be (Lu.21:16-24). His later descriptions of the last days say nothing about persecution. Muslims killing Christians isn’t a sign of the last days, persecution has been going on since the first days (Rom. 8:36).
Since Antichrist will reinstate Judaism after the Rapture, the seducing spirits will also command to abstain from meats to get the world ready for Leviticus 11. Grace believers will swallow it because many believe it is a healthier diet and they also believe Muslims killing Christians is a sign of the last days and so want to be healthy to enter that time of distress. But the Jews weren’t healthy in the wilderness (Ps.105:36,37) because of their diet as some say, they ate manna (Ex.16:35) but because of the promise of God (Deut.7:12-15). They didn’t conquer the Canaanites because they were healthy but also because of God’s promise (Deut.7:12,24).
God gave that diet only to remind them to stay separate from unclean Gentiles (Lev.20:24,25). Those “who believe and know the truth” (ITim.4:3 cf. 2:4) that we are not under the law of Leviticus 11 should receive all foods. Every creature of God is “good” (v.4 cf. Gen.1:20,21). That diet isn’t healthier or God wouldn’t have told Noah he could eat all animals to start the human race over (Gen.9:3). Now the foods God set apart as unclean are clean, just as the people He set apart as unclean are now clean. Both are “sanctified” (ITim.4:5 cf. Rom.15:16).
The “brethren” who needed to be reminded of this in Ephesus where Timothy was pastoring were those teaching the law (ITim.1:6,7). Under the law, a “good minister” (ITim.4:6) reminded people of the words of Leviticus 11, now he reminds people we are not under that law. Under the law, Leviticus 11 was “good doctrine” (ITim.4:6), but today grace is good doctrine. Under the law commanding to abstain from meats was the doctrine of God, today it is a doctrine of devils.
Finally, foods today are sanctified by the Word (ITim.4:5) because the Word through Paul says you can eat all foods, but it is also sanctified by “prayer” (v.5) as you give thanks for it as Paul did (Acts 27:18-35), even amid the storms of life as he did, even when it doesn’t look like there’s anything to be thankful for as he did.