And there was Anna, a prophetess... which departed not from the temple, but served God with fastings and prayers night and day (Luke 2:36-37).
No doubt by praying we learn to pray, and the more we pray the oftener we can pray, and the better we can pray. He who prays in fits and starts is never likely to attain to that effectual, fervent prayer which availeth much.
Great power in prayer is within our reach, but we must go to work to obtain it. Let us never imagine that Abraham could have interceded so successfully for Sodom if he had not been all his lifetime in the practice of communion with God. Jacob's all-night at Peniel was not the first occasion upon which he had met his God. We may even look upon our Lord's most choice and wonderful prayer with his disciples before His Passion as the flower and fruit of His many nights of devotion, and of His often rising up a great while before day to pray.
If a man dreams that he can become mighty in prayer just as he pleases, he labors under a great mistake. The prayer of Elias which shut up heaven and afterwards opened its floodgates, was one of long series of mighty prevailings with God. Oh, that Christian men would remember this! Perseverance in prayer is necessary to prevalence in prayer.
Those great intercessors, who are not so often mentioned as they ought to be in connection with confessors and martyrs, were nevertheless the grandest benefactors of the Church; but it was only by abiding at the mercy-seat that they attained to be such channels of mercy to men.
We must pray to pray, and continue in prayer that our prayers may continue.
--C. H. Spurgeon