Nephi prays that these may be closed to him continually. To the Hebrews, "hell" was either merely the grave; or a region of gloom and misery where the spirits of evil-doers were awaiting the resurrection and final judgment. The gates of hell were the entrance to this region. The spirits of the righteous were in Paradise. But "gates" was also a figurative expression for a town (9, "Lift up your heads, O ye gates and be ye lifted up, ye everlasting doors." "Gates" also means kingdoms or empires, and I believe that Nephi uses the word in that sense. There are on earth two great kingdoms: One is the kingdom of hell, or evil; the other is the kingdom of righteousness. And now he prays that the entrance to the first of these may be closed to him for ever, while he may always have free entrance to the other.
The special lesson of this prayer is that it is safer to keep out of the way of temptation than to rely on one's will power to resist it. "Blessed the man who walketh not in the counsel of the ungodly, nor standeth in the way of sinners, nor sitteth in the seat of the scornful." (2)