kauchaomai

This is the verb behind almost every New Testament mention of boasting, glorying, and taking pride. At its core it means to talk yourself up by pointing to the thing you are confident in, whatever you think makes you stand out or makes you safe. The striking feature is that the very same action can be either disastrous or entirely right, depending only on what the person points to.

The New Testament keeps returning to one dividing line. When people boast in themselves, in their own record, their religious credentials, or their human advantages, the act is condemned as plain pride, because it claims credit that is not theirs and leaves God out. When the identical boasting is aimed away from self and toward God or the Lord, it becomes something good: a confident, open gladness in God that sits very close to worship. Paul makes this his deliberate theme, quoting the line let the one who boasts, boast in the Lord.

A third strand is harder to label, and it is almost entirely Paul writing about himself. Cornered by rivals, he boasts about his churches, his hardships, and even his weaknesses, then turns that boasting straight back toward God, calling it foolish even as he does it. It is the same word and the same act, used here as a defense rather than as either bare pride or simple praise.

Because one verb has to cover self-confidence, glad confidence in God, and Paul's pointed self-defense, no single English word fits every time. Translators rotate among boast, glory, take pride, exult, and rejoice, and the right shade has to be read from what is being boasted in.