Mormon told of the conditions that led to the people’s repentance. He wrote of the beginnings of prosperity that witness to the sincerity of that repentance. Now he declares the final stage of their change of heart. They enter into a covenant.
The covenant appears to be repeated. In verse 31 “they themselves had entered into a covenant with God to serve him and keep his commandments.” In the very next verse, we again have “entered into a covenant with God … to serve him and keep his commandments.” The only difference is that in verse 31 the people are more generic. In verse 32 it is specifically Limhi as the king and, therefore, representative of his people. Perhaps the repetition is for emphasis. Perhaps the addition of Limhi emphasizes that it is an official act on behalf of the people.
The phrase “also many of his people,” seems to exclude some from the covenant. There is no indication that there were any who resisted, and the hope of temporal salvation was much more likely to have been universal. I suggest that the intent was to focus on Limhi and his people, not to suggest that there were any who dissented.