Studies in Genesis 1
The earth brought forth vegetation, plants yielding seed according to their own kinds, and trees bearing fruit in which is their seed, each according to its kind. And God saw that it was good. (Genesis 1:12 ESV)
Why does God repeat Himself? He has already said “Let the earth sprout vegetation, plants yielding seed, and fruit trees bearing fruit in which is their seed, each according to its kind, on the earth” (Genesis 1:11 ESV). Perhaps He is not repeating Himself. Instead He is announcing His plan in one statement then seamlessly executing His plan.
Theology suggests when God states something it is done. He does not speak just to hear His voice. What He says happens. His plan is finished. This is true for everything God says.
Perhaps there is another reason. Being eternal God sees the beginning from the end and all things in between. His plan includes all that will happen. This has astounding implications.
“The former things I declared of old; they went out from my mouth, and I announced them; then suddenly I did them, and they came to pass. Because I know that you are obstinate, and your neck is an iron sinew and your forehead brass, I declared them to you from of old, before they came to pass I announced them to you, lest you should say, ‘My idol did them, my carved image and my metal image commanded them.’” (Isaiah 48:3-5 ESV)
God knew those created in His image would rebel against Him and declare Him powerless. So He tells us what He has done and will do. There is no excuse or made up reason to believe otherwise. He works for Himself yet is mindful of those created in His image.