Amulek has a dual meaning in “call[ing] upon his holy name.” The first context is that of acceptance of the king, and the second is that of the relationship of the king and his people. The people of the king naturally bring their needs to the king. This political analogy is spiritualized into the prayers that we bring to the king. Amulek is telling the people that they may treat this new king as they would an earthly king. Amulek provides a beautifully crafted exhortation to prayer.
Literary: To understand the structure of the opening section we should reprint it without the versification apparatus:
Yea, cry unto him for mercy for he is mighty to save.
Yea, humble yourselves, and continue in prayer unto him.
Cry unto him when ye are in your fields, yea, over all your flocks.
Cry unto him in your houses, yea, over all your household, both morning, mid-day, and evening.
Yea, cry unto him against the power of your enemies.
Yea, cry unto him against the devil, who is an enemy to all righteousness.
Cry unto him over the crops of your fields, that ye may prosper in them.
Cry over the flocks of your fields, that they may increase.
Amulek makes his point through several paired couplets. Each of the couplets has the same general structure. Each consists of an initial statement and a concluding statement. The first line of the couplet agrees in theme with the theme of the second couplet. The conclusion to this set comes when Amulek begins to expand the couplets with interjected amplifications. Amulek’s statement of these couplets might have been extemporaneous, but it is also probable that Amulek is citing something that he expects his audience to understand. This scans like a poetic text, or perhaps a hymn with which his audience might be familiar. Under this possibilitiy, Amulek begins by citing the text, and then ends by expanding the text to hammer home his point.