The first part of this verse is similar to the two parts of the previous verse. It contains a statement that is true, and it may have been a Corinthian slogan, but a qualifier follows. Food is not a matter of spiritual significance for the Christian, except that gluttony is a sin. As far as what we eat goes, we may eat anything and be pleasing to God ( Mark 7:19). He has not forbidden any foods for spiritual reasons, though there may be physical reasons we may choose not to eat certain things. Both food and the stomach are physical and temporal. Paul may have referred to food here, not because it was an issue, but to set up the issue of the body and sexual immorality. However, gluttony and immorality often went together in Greek and Roman feasts. So gluttony may have been an issue. [1] As food is for the stomach, so the body is for the Lord. [source][source][source]
"Not only are meats made for the belly, but the belly, which is essential to physical existence, is made for meats, and cannot exist without them." [2][source]
The same is not true of the body and fornication. Paul constructed his argument like this. [source][source][source]
Proposition1:Part1: Food is for the stomach [3], and the stomach is for food [4].Part2: God will destroy the stomach [5] and the food [6]. [source][source][source]
Proposition2:Part1: The body is for the Lord [3] (not for sexual immorality), and the Lord is for the body [4].Part2: God has raised the Lord [5], and He will raise us [6] (by His power). [source][source][source]
One might conclude, and some in Corinth were evidently doing Song of Solomon , that since sex was also physical and temporal it was also irrelevant spiritually. [11] However this is a false conclusion. The body is part of what the Lord saved and sanctified. Therefore it is for Him, and we should use it for His glory, not for fornication. Furthermore the Lord has a noble purpose and destiny for our bodies. He is for them in that sense. [source][source][source]
The Lord will resurrect the bodies of most Christians in the future, all but those that He catches away at the Rapture ( 1 Thessalonians 4:17). The resurrection of our bodies shows that God has plans for them. Some in Corinth did not believe in the resurrection, but Paul dealt with that later (ch15). Here he simply stated the facts without defending them. [source][source][source]
"The body of the believer is for the Lord because through Christ"s resurrection God has set in motion the reality of our own resurrection. This means that the believer"s physical body is to be understood as "joined" to Christ"s own "body" that was raised from the dead." [5][source]