Love Endures by Diligent Prayer

As the war against their enemies raged on, Mormon and his son Moroni became separated for a time, fighting on different fronts. In the midst of fierce battles, Mormon took the time to write a letter to Moroni. Though distance and circumstances separated father and son, Mormon wanted to encourage Moroni to keep the faith and to remain diligent in following Jesus. Mormon reminded his son about the importance of prayer with these words:

And the remission of sins bringeth meekness, and lowliness of heart; and because of meekness and lowliness of heart cometh the visitation of the Holy Ghost, which Comforter filleth with hope and perfect love, which love endureth by diligence unto prayer, until the end shall come, when all the saints shall dwell with God.
--Moroni 8:26

Praying with diligence is to be steady, persistent and energetic in prayer. Effective prayers are not flashes in the pan. 

Prayer is specifically required to receive and maintain charity, the pure love of Christ. Without diligent, constant, effective, Spirit-guided prayers, Moroni could not have charity, and neither can I. 

Why is the connection between praying and charity so vital? Because charity is based on revelation. Charity is Christ's pure love, exercised according to His will. While I may do some good things of my own free will, the best good is accomplished when I relinquish my will to God and do as He wants instead of as I want. 

I see many circumstances around me that cry out for help, but only God knows what needs to be done in each case. I may see a thirsty man, and since I have two bottles of water in my pack, I think I should give him one. What I don't know, however, is that a person right behind me has a stingy heart and has only one bottle of water, and God has put the thirsty man in that person's path to teach him about sacrifice. So, if I give my water, I have thwarted God's plan and robbed another person of an important lesson. Without the guidance of the Holy Ghost, my altruistic acts may be exactly what God doesn't want. 

Prayer is the means to attune me to the Lord and His will. If I do not talk to God, He will not talk to me. Thus, without prayer, I cannot have true charity.