I read the following, written by John Harder, in a newsletter from Evangelical Tract Distributors.
Most Christians have heard of George Muller and his adventures of faith. But faith has a co-worker, and that is prayer. At the age of thirty-eight, he began to pray persistently for the salvation of five individuals. Every day, come rain or shine, he pleaded for their salvation.
Eighteen months passed before the first accepted the claims of Christ. He thanked God and continued praying for the other four. It was five years before the second person reconciled with God. Muller continued his daily prayers. Six years lapsed for the third. Of the last two he confidently wrote, “They are not converted yet, but they will be.” In 1887, fifty-two years after he had begun to lay their names before the throne of grace, they too were saved.
This account really convicts me of how lacking my prayer life can be. How often do I give up in prayer after only a few times. How much should I continue praying, knowing that God answers prayer. How many can yet be saved if we only pray for them every day!
Hear my prayer, O LORD, give ear to my supplications: in thy faithfulness answer me, and in thy righteousness. — Psalm 143:1 (KJV)