Albert Barnes Commentary 1 Thessalonians 5:24

"Faithful is he that calleth you, who will also do it." — 1 Thessalonians 5:24 (ASV)

Faithful is he that calleth you. That is, your sanctification after all depends on Him, and as He has begun a work of grace in your hearts, you may depend on His faithfulness to complete it. (See 1 Thessalonians 4:3; Philippians 1:6; 1 Corinthians 1:9).