We come to celebrate the Mass to commemorate the sacrifice of the body and blood of Jesus. Jesus who offered Himself on Calvary now offers Himself to us at each Mass.
And while they were at supper, Jesus took bread and blesses it and broke the bread and gave it to His disciples and said,
“Take this, all of you and eat it: this is my Body which will be given up for you.”
And taking the chalice He gave thanks and gave it to them saying,
“Drink you all of this. For this is the cup of my Blood, the Blood of the new and everlasting covenant. It will be shed for you and for all so that sins may be forgiven."