God’s will [according to Jesus] is not unalterable. The Father of Jesus is not the immovable, immutable God who ultimately can only be described in negations. He is not the God to whom it is pointless to pray, but a gracious God who hears prayers and intercessions, and who in his compassion is able to self-repeal his holy will. Above the holiness of God, Jesus places the grace of God.
Joachim Jeremias, The Proclamation of Jesus.