We offer ourselves to him as the Church he formed,and join with him in the sacrifice He made for us/ We are called to be united with Christ as Priest and as Victim.In SC (Sacrosanctum Convivium) we should not only join with the Priest in offering the ‘Immaculate Victim’ but also that they should offer themselves.Christ comes to us under the appearance of Bread and Wine and it is spiritucally transformed into what John says is the Bread of Life (6:35) (He who eats this Bread and drinks my blood has eternal life, and I will raise him up on the last day**)The Eucharist is the New Passover in which God’s new and greater liberation is celebrated and Christ himself is our Passover Meal.;As the living Father sent me and I live because of the Father,so he who eats me will live because of me (CCC1391)
So to quoteE.L.Mascall in Corpus Christi The Whole Christ offers the Whole Christ.