Did the disciples understand the resurrection when they saw Jesus on the Sea of Galilee?
No, the disciples did not yet fully understand the resurrection. Although they recognized Jesus in His resurrection body, the reality had not fully locked in. They still had not contemplated the whole idea that Christ had been raised from the dead.
Les explains that in John 21, the disciples were on the Sea of Galilee. Even though they recognized Christ in His resurrection body, the truth had not yet locked in; they still could not contemplate the whole idea of Christ being raised from the dead. Jesus met them at breakfast time, asked if they had any food, and they said no. He told them to cast the net on the right side, and they caught a multitude of fishes—153 great fishes—yet the net was not broken, unlike the earlier time when it broke. So the sign of this miracle was the unbroken net.
After these things Jesus shewed himself again to the disciples at the sea of Tiberias; and on this wise shewed he himself.
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