"Bone Pastor, panis vere, Jesu nostri miserere, Tu nos pasce, nos tuere; Tu nos bona fac videre In terra viventium: Tu qui cuncta scis et vales, Qui nos pascis hic mortales, Tuos ibi commensales Cohæredes et sodales Fac sanctorum civium." The Fathers[106] with great zeal insist that the physical Body of Christ in the Eucharist, being one in all the receivers, is a principle of unity of Christ's mystical Body. St. Augustine especially dwells upon this effect in Christ's mystical Body, but the effect presupposes the cause, which is that physical Body of Christ received by each. Take an instance of the first statement, that is, the presence of Christ's physical Body, in St. Chrysostom. Commenting on the words, "How can this Man give us His flesh to eat?" he says, "Let us learn what is the marvel of the mysteries, what they are, why they were given, and what is their use. We become, He says, one body, members of His flesh and of His blood. Let those who are initiated follow my words. That we may be so, then, not only by charity but in actual fact, let us be fused with that Flesh. For it is done by that Food which He bestowed on us in the desire to show us the longing which He had for us. He mingled Himself with us, and made His Body one mass with us, that we may be one thing, as a body united with its head. This is what Christ did for us, to draw us to closer friendship and to show His own longing for us; He granted those who desired Him, not only to see Him but to touch Him, and to eat Him, and to fix their teeth in His Flesh, to be joined in His embrace, and to satisfy all their longing. Parents often give their children to be nourished by others; I not so, but I nourish you with My own Flesh; I set Myself before you. I wished to become your Brother, I have partaken of flesh and blood for you; again, I give to you that Flesh and Blood whereby I became your kinsman."[107]