This way of making man bears witness to God's goodness and his rationality, for in our God these always work together . . . It was necessary that there should exist something worthy of knowing God. And could anything be thought of so worthy, as God's own image and likeness? This too is beyond doubt both good and rational. So it was necessary that God's image and likeness should be given free will and the ability to do things for themselves.
Tertullian, Against Marcion 2.6 (Evans, 102-103, updated)