Verses 10 and 11 provide an interesting contrast, for verse 11 is presented as flowing from the event in verse 10. That is, the faith of Enos which begins "to be unshaken" comes as a result of the "voice of the Lord" came into Enos' mind. Presented this simply, there is no question but that hearing the voice of the Lord might increase one's faith. In this case, however, it appears that it really was the hearing of the voice rather than the message of the voice that had this effect on Enos.
The Lord does speak to Enos in direct response to his query about his brethren, but the Lord's response is not what one might expect. We might expect that Enos would procure some promise about the future of his people, or at least their current temporal state. The Lord responds with the promise of the Land, not the people.
The promise of the Land is preserved, and the people benefit in it to the degree of their righteousness. This was the covenant with Lehi, and the Lord does not change it for Enos. Enos receives no promise other than that contingent upon the righteousness of the people. Indeed, the Lord's final promise is that he will visit the wickedness of the Nephites upon their heads. This fairly bleak picture of the future is apparently well understood by Enos, as we will see in verse 13.