Laman and Lemuel have blamed Yahweh for being uncommunicative. Nephi confronts that accusation. Fresh from his experience with the Spirit, Nephi knows that Yahweh communicates, so there must be a different reason that Laman and Lemuel do not receive answers. It is interesting that Nephi does not tell them that they need to ask, but he rather accuses them of not keeping the commandments. We do not know if there were specific commandments that Nephi refers to but has not listed in his text. In the information that we have, Laman and Lemuel are simply guilty of not asking. That may be the sin to which Nephi refers, but perhaps there were others. It is more likely, however that the particular sin is the hardening of the hearts. In verse 11 Nephi tells his brothers that answers come if they do not harden their hearts (and if they then ask).
The contrast between Nephi and Laman and Lemuel at this point is instructive. Laman and Lemuel believe in God, but not one who communicates. They have made no effort to receive understanding from God. They wonder and ponder, but rely upon their own resources.
Nephi both asked and received. Although the record is silent on this point, there is no indication that Nephi spent several days in the desert preparing to ask his question. As he pondered Lehi’s dream, apparently immediately after Lehi recounted it, his desire to know crystallized and he was carried away to his own mount of revelation. He was immediately worthy of an answer. Even had Laman and Lemuel asked, the hardness of their hearts would have precluded the type of answer that Nephi received. The preparation that Nephi made for his vision was a development of character over his young years.