The decree of God to reduce this possibility of creation to act, or the creative purpose, is likewise eternal; since all divine acts are in eternity, and there is no process of deliberation or progress from equilibrium to determination possible in the unchangeable God. God is _actus purissimus_, most pure act, and there is in him nothing potential or reducible to act which is not in act from eternity; since in him there is no past or future, and no succession, but _tota, simul ac perfecta possessio vitae interminabilss_, a complete, simultaneous, and perfect possession of interminable life.
The necessity of his own self-existent being does not determine him to the creative act, but merely to the exercise of supreme omnipotence in choosing freely between the contemplation of creation in its ideal archetype alone, and of creation in its ideal archetype determined to outward actual expression. The inward life of God is necessary, and the interior act of beatific contemplation is of the essence of the divine being. Nothing beyond this, or outside of the interior essence of God, can be necessary, and the creation cannot therefore be necessary, or it would be included in the idea of God, and be identical with the essence of God. God does not create, therefore, by necessity of nature, but by voluntary choice. It is the only exercise of voluntary choice possible to him. It is a choice, however, which though free is determined from eternity. He might have eternally chosen the contrary, that is, to leave the possible creation unactualized in its ideal archetype. He did eternally choose, however, to create.
The learned expositor of St. Thomas, F. Billuart, says that the purpose to create is communicated by the Father to the Word, concomitantly with the intelligence of the divine essence by which he is generated. [Footnote 1] Creation is no afterthought, no capricious or sportive play of omnipotence, like the _jeu d'esprit_ which a poet throws off from a sudden impulse of fancy. The creative purpose has been the theme of the mysterious communications of the three persons of the blessed Trinity, from all eternity. In God, purpose and act, consultation and decree, are one. The decree of creation and the creative act are identical. The creative act, therefore, _a parte Dei_, is eternal. It is an illusion of the imagination to conceive of time as having existed before creation. "In the beginning, God created the heavens and the earth." That beginning was the first moment of time, which St. Thomas says God created when he created the universe. Time is a mere relation of finite entities to each other and to infinite being, arising from their limitation. The procession of created existences is necessarily in time, and could not have begun _ab aeterno_ without a series actually infinite, which is impossible. Nevertheless, the first instant of created time had no created time behind it, and no series of instants behind it, intervening between it and eternity, but touched immediately on eternity.