James 5:15 does express the believer’s forgiveness using future tense. However, James is simply presenting a hypothetical situation (“if he has committed sins”) and assuring his readers that such a person will be forgiven in that scenario. This passage is intended to be comforting for anyone who might be afraid of a future struggle. Any sin committed will be forgiven because of the finished work of Jesus Christ, once for all (Hebrews 10:14).