As we are humble before the Lord, we gain some understanding. In the case of the Ammonihahites, that first step would be an acceptance of the Lord as the Atoning Messiah. After that acceptance, they must exercise faith on him. Hope as a principle is not well defined in the scriptures, but as it is used in Paul is linked with an understanding of and faith in the nature of the next world. In 1 Corinthians Paul uses an agrarian metaphor:
1 Cor. 9:10
10 Or saith he it altogether for our sakes? For our sakes, no doubt, this is written: that he that ploweth should plow in hope; and that he that thresheth in hope should be partaker of his hope.
Paul's farmer plows in hope. The very idea of a farmer planting is an example of current actions that are done in anticipation of future reward. This future reward is the domain of hope in Paul. When Paul uses that term as a principle, it is a principle that looks forward to the future benefit as a guide to our current actions.
Col. 1:27
27 To whom God would make known what is the riches of the glory of this mystery among the Gentiles; which is Christ in you, the hope of glory:
It is very clear that the promise of the gospel is not worldy riches, but rather the riches of the glory. This is inherently a future reward, and for the early Christians Paul tells them that it is known to them but a mystery to the Gentiles. He tells them that these riches of the glory come to them through Jesus Christ, and that through Jesus the have the hope, or expectation, of that future glory.
1 Thes. 4:13-1413 But I would not have you to be ignorant, brethren, concerning them which are asleep, that ye sorrow not, even as others which have no hope. 14 For if we believe that Jesus died and rose again, even so them also which sleep in Jesus will God bring with him.
Here Paul's hope is not a glory, but a state which occurs in the future. The resurrection is necessarily something that comes after our death, a time period of mystery and wonder to most of the inhabitants of earth. Those who do not know of the mission of Christ have no hope, they have no future expectation of life. It is in this future context that we may understand yet another phrase from Paul:
1 Cor. 15:19
19 If in this life only we have hope in Christ, we are of all men most miserable.
Paul's contrast here is the unstated parallel verse which indicates that because we have hope in Christ in the world to come, we might be of all men most happy. This hope is not an earthly promise, but one which is fulfilled in this life. If we have hope in Christ only in this life, we are to be disappointed, for often the way of Christ is more difficult to tread that the way of the world. We walk that path for the vision of the future, just as the farmer plants now for the vision of the later harvest.
Alma's hope is similarly one of an expectation of the future promise rather than the earthly promise.