I suspect that when we get to Heaven, people will introduce themselves to us whom we never knew upon the earth. "I want to thank you for that prayer you prayed for me on December 31, 2012," they'll say with a grateful heart and smile. "The Lord did wonderful things in my life and the life of my family in response to your intercession."
In all honesty (and we will be completely honest in Heaven!), we'll have to admit, "Dear Sister, it's kind of you to say that, but I must confess that I didn't know you during our earthly lifetime. You must be mistaking me for someone else." Our fellow believer will persist, however. "No, it was you," she'll insist. "You passed by me in a store on that day, and the Holy Spirit caused something about me to get your attention. And you responded. You prayed, Lord, I don't know that person or anything about them. But You know all. I therefore ask You to work in their heart and life according to Your glory and their need." Our sister will conclude, "Our Heavenly Father answered that prayer, and it will take me awhile, a long while, to tell you how much He did in and through my life because of your request. Thankfully, we have a long while, so here's what happened..."
The most wonderful thing about such "passing prayers," offered briefly and seemingly inconsequentially, is that the Lord so obviously receives all the glory for them. This is true of all genuine prayer, of course, but those intercessions offered with little knowledge and few words will likely be the ones through which His greatest work is done. Thereby, "the Lord alone shall be exalted in that day" (Isaiah 2:11). The pray-er will be blessed in his praying, the pray-ee will be blessed in the answer, and together both will fall before their Heavenly Father to praise Him for both the gift of prayer and the gift of answered prayer.
The Lord Jesus warned that "long prayers" can involve little more than the pretentious attempt to garner attention (Mark 12:40). Short prayers, however, frequently offered in the knowledge that, by definition, the very act of praying comprises our admission of weakness in both knowledge and capacity, may well lead to the most powerful Divine response. Only God sees into the heart of people, wherein "the issues of life" truly exist (Proverbs 4:23). He alone knows our true need, and the simple requests that acknowledge and display our awareness thereof may result in our finest "hour" of intercession.
Certainly, long seasons of genuine prayer happen in our lives. We give thanks for them. However, seemingly passing prayers, inspired and enabled by the Holy Spirit along the byways of life, accomplish much for the glory of God and the blessing of others. Let us expect that in this day, He will lead accordingly, foreshadowing another day, in another time and another place, when some brother or sister will approach us on a glimmering street of gold. "I want to thank you for that prayer you prayed for me on December 31, 2012..."
"Pray without ceasing."
(I Thessalonians 5:17)