Alma 4:13-14

Now this was a great cause for lamentations among the people, while others were abasing themselves, succoring those who stood in need of their succor, such as imparting their substance to the poor and the needy, feeding the hungry, and suffering all manner of afflictions, for Christ’s sake, who should come according to the spirit of prophecy; Looking forward to that day, thus retaining a remission of their sins; being filled with great joy because of the resurrection of the dead, according to the will and power and deliverance of Jesus Christ from the bands of death.

A recurring theme in the Book of Mormon is the principle of retaining the remission of our sins through selfless service in caring for the poor. We do not buy our way into heaven with good deeds, but we please our Father when we learn to have compassion and use the gifts he has given us to bless others. We show our desire to serve him through our service to others, and he rewards our desires with mercy.

Mosiah 4:20

And behold, even at this time, ye have been calling on his name, and begging for a remission of your sins. And has he suffered that ye have begged in vain? Nay; he has poured out his Spirit upon you, and has caused that your hearts should be filled with joy, and has caused that your mouths should be stopped that ye could not find utterance, so exceedingly great was your joy.

God answers our sincere prayers for forgiveness readily and instantly. He does not leave us dangling endlessly on the hook, wondering if he hears, wondering if he cares, wondering if he even knows who we are. When we are humble, and approach him in lowliness of heart, he answers surely and quickly with peace. That does not mean that all mortal consequences are extinguished in that moment, but mortal guilt and anguish can be swept away, and our hearts can be filled with hope and peace.