What is God's fiat?

Answer 1

The world, creation, Fiat means to command something to be done and have it doen without effort or even material. "In the Beginning God created the Heavens and the Earth.....""...... He commanded, let there be light, and there was light, and he saw that it was good." and so on. does that help?

Answer 2

God's fiat refers to God's command or declaration that brings about creation or change. This concept is often used to describe God's ability to bring things into existence simply by decreeing it to be so. In Christianity, the phrase "fiat lux" (let there be light) is often used to refer to God's act of creation in the book of Genesis.