1 Nephi 9

I'm beginning to think that one of the themes of the Book of Mormon may as well be the explanation of it's purpose in existing. Chapter 9 is speaking about the two separate plates Nephi wrote and named after himself. The small plates and the large plates. The small plates holds the "ministry of [his] people" (1 Nephi 9:3). The large plates contant "an account of the reign of the kings, and the wars and contentions of [his] people" (1 Nephi 9:4).

Nephi wasn't really sure why he was told to create two entirely separate plates, but he did it because of a "wise purpose in [the Lord]" (1 Nephi 9:5).

We can also practice obedience as Nephi did. Elder Marvin J. Ashton once said:

Sometimes when we are asked to be obedient, we do not know why, except the Lord has commanded. Nephi followed instructions even though he didn’t fully understand the wise purpose. His obedience resulted in blessings to mankind all over the world. By not obeying our present-day leaders, we plant our seeds in stony places and may forfeit the harvest (in Conference Report, Oct. 1978, 76; or Ensign, Nov. 1978, 51).

We can exercise this type of obedience in a smaller extent with our parents, teachers and leaders. When my parents ask me to take out the trash or clean the living room or some sort of thing, as a child you may not know why. But we can act immediately anyways. When the Lord asks us to do something, we definitely should do it. The Lord knows everything and he wants the best for us.

As verse 6 says:

But the Lord knoweth all things from the beginning; wherefore, he prepareth a way to accomplish all his works among the children of men; for behold, he hath all power unto the fulfilling of all his words. And thus it is.

Elder Neal A. Maxwell also contributed to that topic:

Some have sincere faith in the existence of a God but not necessarily in a revealing and omniscient God. Other sincere individuals question God’s omniscience, wondering, even though respectfully, whether even God can know the future. But an omniscient and revealing God can at any present moment disclose things future. This is possible because ‘in the presence of God, . . . all things for their glory are manifest, past, present, and future, and are continually before the Lord’ (D&C 130:7). Thus God ‘knoweth all things, for all things are present before [his] eyes’ (D&C 38:2). He told Moses, ‘There is no God beside me, and all things are present with me, for I know them all’ (Moses 1:6). 

No qualifiers on the scope of God’s knowledge appear in holy writ. Instead, we read: ‘O how great the holiness of our God! For he knoweth all things, and there is not anything save he knows it.’ (2 Nephi 9:20). (If Thou Endure It Well [1996], 46).

The Lord knows everything. Why wouldn't you want to be obedient to Him? There really isn't a reason why you shouldn't. He wants what is best for us. He knows how we can get there. He prepares a way and tries to guide us down it. Why wouldn't you want to listen to his instruction?