In 1 Corinthians 8:1 Paul tells the Corinthian knowledgable that their so-called knowledge “puffs up” while love “builds up” (οἰκοδομεῖ). This, of course, is in reference to the eating of food offered to idols. Some of the Corinthians without this so-called knowledge are scandalized by this behavior and Paul’s point is that love for the weaker brother will not do anything to violate their conscience.
By the time we get to vs. 10 we see that if a weaker brother sees someone with this so-called knowledge eating idol food in an idol’s temple then they will be “encouraged” (οἰκοδομηθήσεται) to do the same. This is the same verb used in vs 1 to say that love “builds up.” Paul continues in vs. 11 to say that by this “knowledge” the weaker person is destroyed. There’s an irony here in that the same knowledge that puffs up can also build up but it does so for the ruin of the one being built up. The building up that comes through love is for their strengthening.
There’s also something to be said about the differences in voice between the building up, encouraging, and destroying of vss. 1, 10, 11 but I’ll save that for another post.