"For God, who commanded the light to shine out of darkness, hath shined in our hearts, to give the light of the knowledge of the glory of God in the face of Jesus Christ." (2 Corinthians 4:6)
Even a superficial reading of the account of creation in Genesis 1 and 2 impresses the reader with the idea of suddenness. God simply called the universe into existence from nothing and then quickly set about the rapid formation of certain features, interspersed with other direct creative acts. All of the events, whether creative or formative, seem to have happened over a brief period of time, such as the formation of the plants (Genesis 1:12), the animals (v. 20), and the sun and stars (v. 16).
This is especially true of the creation of light. "And God said, Let there be light: and there was light" (1:3). No slow and sporadic arrival of light from distant stars is mentioned, nor a gradual heating up of the sun as interstellar gas collapsed and fused. Some evangelical advocates of the old-earth concept hold that God slowly cleared the atmosphere of left-over interstellar, dust which allowed the light from the sun and stars to penetrate to the earth.
But, if Scripture alone is our authority, then it happened suddenly and spectacularly. As discussed in our text, it happened just as suddenly and just as supernaturally as a new creature is created out of a dead creature at the moment of salvation. Sanctification may be a life-long matter, but "if any man be in Christ, he is a new creature" (2 Corinthians 5:17), literally creation. No more time is required for the transformation than for darkness to turn into light at the Creator's command. JDM