Blessed are ye that sow beside all waters… – Isaiah 32:20

Some one may say, “I would not mind the moral condition of the people, but it is their surroundings that are the trouble. What is the use of trying to save a man while he lives, as he does, in such a horrible street, in one room? What is the use of seeking to raise such and such a woman while she is surrounded, as she is, with such examples? The very atmosphere seems tainted.” Just so, dear friend; while you observe the winds, and regard the clouds, you will not sow, and you will not reap. You will not attempt the work, and of course you will not complete what you do not commence. You can go on making all kinds of excuses for doing nothing with certain people, because you feel or think that they are not those whom God is likely to bless. I know this to be a common case, even with very serious and earnest workers for Christ.

Let me carry this principle, however, a little further. You may unduly consider circumstances in reference to the business of your own eternal life. You may, in that matter, observe the winds, and never sow; you may regard the clouds, and never reap. “I feel,” says one, “as if I never can be saved. There never was such a sinner as I am. My sins are peculiarly black.” Yes, and if you keep on regarding them, and do not remember the Saviour, and His infinite power to save, you will not sow in prayer and faith. “Ah, sir; but you do not know the horrible thoughts I have; the dark forebodings that cross my mind!” I know what I feel myself, and I expect that your feelings are very like my own; but be what they may, if, instead of looking to Christ, you are always studying your own condition, your own withered hopes, your own broken resolutions, then you will still keep where you are, and you will neither sow nor reap. ~ C.H. Spurgeon

https://www.blueletterbible.org/comm/spurgeon_charles/sermons/2264.cfm