Symbolizing abundance, 153 can even represent an OVERFLOW blessing from God. The Bible states the disciples marvelled at the fact that their net held together even though it contained so many large fish (John 21:11)! Additionally, the catching of such a large amount of fish happened only after Christ became involved in the work. This is a subtle (or perhaps not so subtle!) reminder that without Christ the disciples' (and any believer's) attempts to accomplish something great on their own will fail, but that with Jesus all things are possible (John 15:5).
Lastly, the 153 fishes is reminiscent of a previously abundant catch Peter, Andrew, James and John experienced when they were first called to follow Christ and become fishers of MEN (and not food). Given the disciples were trying to go back to their pre-conversion employment when the miracle occurred, it likely reminded them that they now worked for God whose will it still was for them to catch men and not fish.
Additional information on the Biblical Meaning of the number 153
We discover something quite interesting when we look at how many people, in the Gospel accounts, Jesus personally blessed.
The book of Mark records Christ, on a total of three occasions, personally blessed three people. These events were the healing of a man with an unclean spirit (Mark 1:23), healing a man who was deaf (Mark 7:32) and making whole another who was blind (Mark 8:22). Matthew, however, writes that on 23 occasions Jesus blessed a total of 47 people. Some of those whom he bestowed God's grace to include a leper (Matthew 8:2), a non-Israelite woman and her daughter (Matthew 15:22), Mary Magdalene (Matthew 27:56) and Joseph of Arimathaea (Matthew 27:57). Luke writes that on 14 occasions 94 people were blessed. They include the seventy disciples sent out to preach and heal (Luke 10:1), ten lepers cleansed at the same time (Luke 17:12) and Zaccheus (Luke 19:2). Lastly, the apostle John bears record of 8 incidents where 9 people were helped by Jesus. Nicodemus (John 3:1), the woman accused of adultery (John 8:11) and Lazarus (John 11) are among those personally touched by the Savior of mankind.
All told, the Lord directly blessed a grand total of 153 people in 48 separate incidents!