O Thou that hearest prayer, unto Thee shall all flesh come. – Psalm 65:2

It is said that fat men may for a time live on the flesh they have acquired; but there is not a Christian so full of flesh that he can live on old grace. If he waxes fat he kicks, but he cannot live upon his fat. Those who are strong and mighty in themselves cannot exist without prayer. If a man should have the spiritual might of fifty of God’s choicest Christians in himself, he must die, if he did not continue to plow. My brother, cannot you look back and say, “Three or four months ago my prayers were more regular, more constant, more earnest than they are now; but now they are feeble, they are not sincere, they are not fervent, they are not earnest? “O brother, do not ask anybody what is the cause of your grief; it is as plain as possible; you need not ask a question about it. There is the cause; and where is the remedy? Why, in more prayer, beloved. It was little prayer that brought you down; it is great prayer that will lift you up. It was lack of prayer that brought you into poverty, it must be increase of prayer that will bring you into riches again.

A certain merchant wishes that he were as rich as he used to be; he was wont to send his ships over to the gold country, to bring him home cargoes of gold, but ne’er a ship has been out of port lately, and therefore can he wonder that he has had no cargo of gold? So when a man prayeth he sends a ship to heaven, and it comes back laden with gold; but if he leaves off supplication, then his ship is weather-bound and stays at home, and no wonder he cometh to be a poor man.~ C.H. Spurgeon

https://www.blueletterbible.org/Comm/spurgeon_charles/sermons/0051.cfm