No one sews a piece of unshrunk cloth on an old garment. If he does, the patch tears away from it, the new from the old, and a worse tear is made. And no one puts new wine into old wineskins. If he does, the wine will burst the skins—and the wine is destroyed, and so are the skins. But new wine is for fresh wineskins.”
Mark 2:21-22 ESV
Jesus explains with another 2 examples that when the new one has come and fulfil the needs, why go back to the old way and use the old method? Because indeed Jesus has come to fulfil the Old Testament therefore there was no need to do the old tradition. Jesus has come to forgive the sins of humanity and he stood as the sacrifice for our sin therefore don’t bring the old law and try to forcefully use it as a patch! :) Isn’t it great the fact that we just need to enjoy the new wine in the new wineskin :)
The old is gone and the new has come!