22 Yea, and I say unto you that if it were not for the prayers of the righteous, who are now in the land, that ye would even now be visited with utter destruction; yet it would not be by flood, as were the people in the days of Noah, but it would be by famine, and by pestilence, and the sword.
23 But it is by the prayers of the righteous that ye are spared; now therefore, if ye will cast out the righteous from among you then will not the Lord stay his hand; but in his fierce anger he will come out against you; then ye shall be smitten by famine, and by pestilence, and by the sword; and the time is soon at hand except ye repent.
After testifying to his fellow-residents of Ammonihah that Alma is a prophet of God, Amulek goes on to endorse Alma’s message: they need to repent, or they will be destroyed. He tells them that the only reason they have been spared from the consequences of their bad decisions so far is because of “the prayers of the righteous.” He further warns them that, if they cast out the righteous, then the punishments will come.
This prophecy comes true shortly afterward. The people of Ammonihah drive away all of the men who believe and then murder their wives and children (Alma 14:7-8). Shortly thereafter, their city is attacked by the Lamanites and completely destroyed (Alma 16:1-3).
Mormon affirms to us on at least two other occasions that sinners can be insulated temporarily from the full consequences of their actions and can even be blessed by the prayers of the righteous on their behalf (Alma 62:40, Mormon 5:21). As James taught, “The effectual fervent prayer of a righteous man availeth much” (James 5:16).
Today, I will remember that prayers matter. I will pray for other people, knowing that my prayers on their behalf will be answered. I will also be mindful that I am blessed because other people are praying for me.