The future of both the Nephites and the Lamanites had been revealed through Lehi and Nephi (see 1 Nephi 12; 1 Nephi 15:5). Enos, witnessing those prophecies coming to pass and fearing that because of their wickedness the Nephites might well be destroyed, sought to obtain from the Lord the promise that a record of their doings would be preserved.
Enos’s hope was that such a record would come forth to the edification and blessing of the Lamanites and call them back to the faith of their fathers. Thus his prayers became one with the prayers of his fathers who had sought this same blessing for those of future generations.