Alma has been distinguishing between the first spiritual death and the second, and between the first commandments and the second commandments. The first commandments, of course, are the commandments given to Adam and Eve in the garden, and the second commandments are the ones given to them after they were cast out (v. 31-32). Along this same line of discussion, the first provocation is when Adam and Eve provoked the Lord by disobeying his commandments and thereby bringing about the Fall of man. The last provocation, to which Alma refers, is the provocation of the children of men when they disobey the second set of commandments and thereby are in danger of suffering the penalty of the second spiritual death.
Orson Pratt
"If any should feel disposed to doubt whether the second penalty will be inflicted, let them look at the infliction of the first, during the last 6,000 years. The first death, with all its attendant evils, has extended its ravages among all nations and generations since the first law was broken. If God, then, has fulfilled His word in the first provocation, to the very letter, why should any one suppose that He will not inflict the second death as a penalty of the second provocation?" (Journal of Discourses, vol. 1, p. 330)