What does John 21:7 mean?
Peter, John, and five other disciples (John 21:2–3) ended a night of fishing without any success. The common way to work on a fishing boat in that era involved removing one's outer garments. Though the English term "naked" means entirely lacking clothes, the Greek term gymnos more generally means someone lightly or poorly clothed.As the dawn breaks, the men hear a man standing on shore asking about their catch, telling them to cast on the right side of the boat (John 21:4–6). The result is an enormous haul: so big it can't be pulled on board. John, as he often does, refers to himself indirectly as "that disciple whom Jesus loved" (John 13:23; 19:26; 20:3).
The miraculous results of the man's advice echo a similar incident from the disciples' early days with Jesus (Luke 5:4–6). Recognizing the supernatural power of that event, Peter had reacted in faith (Luke 5:8). Here, the instant appearance of so many fish makes the identity of the man on shore obvious: this is Jesus.
Peter's reaction is typically dramatic. He hastily throws on his outer clothes and jumps into the water so he can swim to shore. The others will follow, as they can, hauling the overloaded net (John 21:8).