2 Nephi 25:16

and after that they have been scattered, and the Lord God hath scourged them by other nations, for the space of many generations, yea, even down from generation to generation, until they shall be persuaded to believe in Christ, the Son of God, and the atonement, which is infinite for all mankind; and when that day shall come, that they shall believe in Christ, and worship the father in his name, with pure hearts, and clean hands, and look not forward any more for another Messiah, then, at that time, the day will come that it must needs be expedient that they should believe these things,

After they are scattered, the Lord God will punish them through other nations. This will happen for many generations. It will go on from one generation to another. Finally they will be led to believe in Christ. He is the Son of God. They will believe in the atonement. The atonement is for all people everywhere. When they believe in Christ, they will worship the Father in his name. They will worship with pure hearts and clean hands. They will stop looking for another Messiah. When that day comes, they should believe these things.

After they’ve been scattered, and the Lord has let other nations punish them for many generations—down through the ages—they’ll finally be persuaded to believe in Christ, the Son of God, and in his atonement, which covers all humanity. When they believe in Christ, worship the Father in his name with pure hearts and clean hands, and stop waiting for another Messiah—then the time will come when they must accept these truths.