John Calvin Commentary John 21:14

"This is now the third time that Jesus was manifested to the disciples, after that he was risen from the dead." — John 21:14 (ASV)

The third time. The number three refers to the interval of time. Christ had already appeared to his disciples more than seven times, but all that had occurred in one day is included in one manifestation. The Evangelist, therefore, means that Christ had been seen by the disciples at intervals, in order to confirm their belief in his resurrection.