A.T. Robertson Commentary James 4:16

"But now ye glory in your vauntings: all such glorying is evil." — James 4:16 (ASV)

In your vauntings (εν ταις αλαζονιαις υμων). Old word for braggart talk (from αλαζονευομα, to act the αλαζων empty boaster Ro 1:30), common in Aristophanes, in N.T. only here and 1 John 2:16.

Glorying (καυχησις). Act of glorying, late word from καυχαομα, good if for Christ (1 Thessalonians 2:19), bad if for self as here.