...God will be 'all in all' (I Cor. 15:28) when we are no longer what we are now, a multiplicity of impulses and emotions, with little or nothing of God in us, but are fully like God , with room for God and God alone. This is the 'maturity' (cf. Col. 1:28) towards which we speed.
Gregory of NazianzusNo one seeing a beautifully elaborated lyre with its harmonious, orderly arrangement, and hearing the lyre's music will fail to form a notion of its craftsman-player, to recur to him in thought though ignorant of him by sight. In this way the creative power, which moves and safeguards its objects, is clear to us, though it be not grasped by the understanding. Anyone who refuses to progress this far in following instinctive proofs must be wanting in judgment. But still, whatever we imagined or figured to ourselves or reason delineated is not the reality of God.
Gregory of NazianzusWe were made for good works (cf. Phil. 1:11) to the glory and praise of our Maker, and to imitate God as far as might be.
Gregory of Nazianzus