Moroni defines a miracle as something that God does and man cannot comprehend (v. 16). He then cites miracles at the time of the creation (v. 17) and at the time of Christ and his Apostles ministering on earth (v. 18). The creation was a miracle that is not comprehended by man because the elements obeyed God’s voice. The Prophet Joseph Smith explained: “Now, the word create came from the [Hebrew] word barau which does not mean to create out of nothing; it means to organize; the same as a man would organize materials and build a ship. Hence, we infer that God had materials to organize the world out of chaos—chaotic matter, which is element, and in which dwells all the glory” (TPJS, 350–51). Moroni does not give an explanation of the miracles performed by Christ and his Apostles. We assume that this was because he knew that a record of their miracles was already upon the abridgment of the plates of Nephi.
God became God by obedience to eternal law, and he is a perfect Being (see Alma 42:22–23). He placed us here and gave us the same opportunity as he had (see 3 Nephi 12:48; Matthew 5:48). His nature is eternal and he cannot change (see Alma 42:22–24; Helaman 13:38). Therefore, he changeth not and is a God of miracles (Mormon 9:19). The reason miracles cease among men is because of their unbelief (v. 20).