John 21:2-4

Verse 3

Peter saith - I go a fishing - Previously to the crucifixion of our Lord, the temporal necessities of himself and his disciples appear to have been supplied by the charity of individuals: Luk 8:3. As it is probable that the scandal of the cross had now shut up this source of support, the disciples, not fully knowing how they were to be employed, purposed to return to their former occupation of fishing, in order to gain a livelihood; and therefore the seven, mentioned Joh 21:2, embarked on the sea of Tiberias, otherwise called the sea of Galilee.

That night they caught nothing - God had so ordered it, that they might be the more struck with the miracle which he afterwards wrought.
Verse 4

Knew not that it was Jesus - Probably because it was either not light enough, or he was at too great a distance, or he had assumed another form, as in Mar 16:12; otherwise his person was so remarkable that all his disciples readily knew him when he was at hand: see Joh 21:12.
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