The words in question occur twice in the last three verses 21-23 of First Corinthians chapter three.

We read: “Hence let no one be boasting in men; for all things belong to you, whether Paul or Apollos or Cephas or the world or life or death or things now here or things to come, all things belong to you; in turn you belong to Christ; Christ, in turn, belongs to God.”​—1 Cor. 3:21-23.

The question may well be asked, What are the evidences of having maturity or at least working toward it?—1 Cor. 1:11; 3:21; 5:1; 3:1-3, 21; 4:1, 2.

Jude here uses the same Greek word for “building” that Paul uses in 1 Corinthians chapter 3, but his point seems to be that we build ourselves up on the foundation of our faith.

 3. What matters did Paul initially deal with in his first letter to the Corinthians?

³ In the long letter Paul wrote to the Corinthians, he first addressed the problem of disunity. (1 Corinthians, chapters 1-4)

To quote Paul’s own words: “I planted, Apollos watered,” for both were “God’s fellow workers.”—1 Corinthians 3:6, 9, 21-23.