What does 1 Corinthians 8:1 mean?

Paul turns the corner from his instruction about marriage and sexuality to a new issue. In previous verses, Paul referred to some letter written to him by the church in Corinth (1 Corinthians 7:1). The issue he discusses here seems to be another topic raised in that earlier message. Based on the context of the following chapters, it's possible that they are challenging his former teaching about eating food that has been offered to idols.

Paul begins to tackle this issue in chapter 8 and then seems to leave it behind in chapter 9 and the first part of chapter 10. Taken as a whole, all three chapters lead up to his final declarations about when it is acceptable for a Christian to eat food that may have been offered to an idol and when it is not.

In challenging him and his former teaching on the issue, the Corinthians may have been the ones to originally say "all of us possess knowledge." Just as Paul seems to quote a phrase in 1 Corinthians 7:1, he appears to do the same in this verse. The believers in Corinth might mean this expression in the sense that they, too, understand this issue and feel qualified to declare it is moral to eat idol food. Paul does not disagree with their initial idea. All believers do possess knowledge about God through the Holy Spirit (1 Corinthians 2:14–15).

However, Paul responds that knowledge alone is not enough. Knowledge on its own merely puffs a person up. This comes from a Greek root word, phuisoo, which literally means to inflate or blow something up, as one would with a balloon. Describing a person, it implies arrogance and egotism. Paul contrasts this with one of several Greek words translated as "love." In this case, he applies agapē, a self-sacrificial love. That kind of love builds people up. As Paul will famously write in chapter 13, someone who has knowledge without love is nothing.

Paul will go on to show that love for others is one reason these Christians must not knowingly eat food offered to idols.