Thanks to Adrian Warnock for this quote about the importance of prayer in Charles Spurgeon's ministry:
WHEN I came to New Park Street Chapel, it was but a mere handful of people to whom I first preached; yet I can never forget how earnestly they prayed. Sometimes, they seemed to plead as though they could really see the Angel of the covenant present with them, and as if they must have a blessing from Him. More than once, we were all so awe-struck with the solemnity of the meeting, that we sat silent for some moments while the Lord’s power appeared to overshadow us; and all I could do on such occasions was to pronounce the Benediction, and say, “Dear friends, we have had the Spirit of God here very manifestly to-night; let us go home, and take care not to lose His gracious influences.”
Then down came the blessing; the house was filled with hearers, and many souls were saved. I always give all the glory to God, but I do not forget that He gave me the privilege of ministering from the first to a praying people. We had prayer-meetings in New Park Street that moved our very souls. Every man seemed like a crusader besieging the New Jerusalem, each one appeared determined to storm the Celestial City by the might of intercession; and soon the blessing came upon us in such abundance that we had not room to receive it.
C. H. Spurgeon, C. H. Spurgeon’s Autobiography, Compiled from His Diary, Letters, and Records, by His Wife and His Private Secretary, 1834–1854, vol. 1 (Cincinatti; Chicago; St. Louis: Curts & Jennings, 1898), 361.