The disciples, especially Peter, were at loose ends. They perhaps were unable to make sense of the implications of the resurrection and could npt see how to procede. So they tried instead to go back to what had once been their lives before they met Jesus … fishing.
As Thomas Wolfe said, you can’t go home again, can’t recover the past. The disciples were unable to catch any fish.
As I neared the end of the Spiritual Exercises online retreat, I realized that I was like the disciples in this passage. Before the retreat, I was an agnostic but the process of those 30 odd weeks changed me. I wasn’t sure how to go forward (still not sure) yet I couldn’t go back to how things had been before the retreat.