That gospel is read on Holy Thursday when we celebrate the Mass of the Lord’s Supper. The story of the wedding at Cana must be understood within the context of Jesus’ ministry at the institution of the Eucharist.
So when he had washed their feet [and] put his garments back on and reclined at table again, he said to them, “Do you realize what I have done for you? You call me ‘teacher’ and ‘master,’ and rightly so, for indeed I am . If I, therefore, the master and teacher, have washed your feet, you ought to wash one another’s feet. I have given you a model to follow, so that as I have done for you, you should also do . Amen, amen, I say to you, no slave is greater than his master nor any messenger greater than the one who sent him. Jn. 13:12-16.