It is in this context of our inability to obey simple and beneficial commands from God that we are “nothing.” Mormon is paralleling language and a concept found in the discourse of Benjamin:
Mosiah 2:22-25
22 And behold, all that he requires of you is to keep his commandments; and he has promised you that if ye would keep his commandments ye should prosper in the land; and he never doth vary from that which he hath said; therefore, if ye do keep his commandments he doth bless you and prosper you.
23 And now, in the first place, he hath created you, and granted unto you your lives, for which ye are indebted unto him.
24 And secondly, he doth require that ye should do as he hath commanded you; for which if ye do, he doth immediately bless you; and therefore he hath paid you. And ye are still indebted unto him, and are, and will be, forever and ever; therefore, of what have ye to boast?
25 And now I ask, can ye say aught of yourselves? I answer you, Nay. Ye cannot say that ye are even as much as the dust of the earth; yet ye were created of the dust of the earth; but behold, it belongeth to him who created you.
Both Benjamin and Mormon understand that the Lord stands ready to bless us if we but follow his commandments. Both of them use the imagery of the dust of the earth to make the point. We may expect that Mormon, who had clearly studied his sources, was aware of Benjamin, and probably used this imagery with a conscious reflection on this earlier and great prophet and king. The dust of the earth in Benjamin is part of the creation of God. God owns it; it is His. Were we truly His, we would obey. The dust obeys. God may command, and the dust “moveth hither and thither.” All we need to do is obey, and we cannot do that as well as the simple dust of the earth.