Bonhoeffer on Matt 26:39ff:
Jesus prays to the Father that the cup pass from him, and the Father hears the son's prayer. The cup of suffering will pass from Jesus, but only by his drinking it. When Jesus kneels in Gethsemane the second time, he knows that the cup will pass by his accepting the suffering. Only by bearing the suffering will he overcome and conquer it. His cross is the triumph over suffering.
Suffering is distance from God. That is why someone who is in communion with God cannot suffer. Jesus affirmed this Old Testament testimony. That is why he takes the suffering of the whole world onto himself and overcomes it. He bears the whole distance from God. Drinking the cup is what makes it pass from him. In order to overcome the suffering of the world Jesus must drink it to the dregs. Indeed, suffering remains distance from God, but in community with the suffering of Jesus Christ, suffering is overcome by suffering. Communion with God is granted precisely in suffering.
Suffering must be borne in order for it to pass. Either the world must bear it and be crused by it, or it falls on Christ and is overcome in him. That is how Christ suffers as vicarious representative for the world. Only his suffering brings salvation. But the church-community itself knows now that the world's suffering seeks a bearer. So in following Christ, this suffering falls upon it, and it bears the suffering while being borne by Christ. The community of Jesus Christ vicariously represents the world before God by following Christ under the cross.
[...] Bearing constitutes being a Christian. Just as Christ maintains his communion with the Father by bearing according to the Father's will, so the disciples' bearing constitutes their community with Christ [...] Jesus called all who are laden with various sufferings and burdens to throw off their yokes and to take his yoke upon themselves. His yoke is easy, and his burden is light. His yoke and his burden is the cross. Bearing the cross does not bring misery and despair. Rather, it provides refreshment and peace for our souls; it is our greatest joy.
(Dietrich Bonhoeffer, Discipleship, pp. 83-84)