Moab is My washpot… – Psalm 60:8

But I keep under my body, and bring it into subjection: lest that by any means, when I have preached to others, I myself should be a castaway. – 1 Corinthians 9:27

There are certain sins which we readily detect in others, which should serve as loud calls to us to correct the same things in ourselves. When a man sees the faults of others and congratulates himself that he is far superior to such, he evidently knows not how to extract good from evil; he is proud and knows nothing. But when we perceive errors in others, and immediately set a diligent watch against falling into the like, then Moab is rightly used, and becomes our washpot. For instance, as to the matter of bodily indulgence? The sinner is a man who puts his body before his soul, and his head where his feet should be; he is therefore a monster in nature. Instead of the world being under his feet, as it is with every good man, he inverts himself, and places his head and his heart in the dust. He lives for the body which is to die and forgets the soul which lives for ever. When therefore you see a drunkard, or an unchaste person, say to yourself, “I must mortify my members, and give my Spiritual nature the predominance. For this I must cry mightily to God, the Eternal Spirit, lest the body of this death prevail over me. I must keep under my body, as the Apostle saith, and bring it into subjection, lest I too become a prey to the same animal passions, which lead sinners captive.” I see the ungodly man putting this poor fleeting world before the eternal world to come; therein he is a fool; but let me take heed that I in no measure imitate him. ~ C.H. Spurgeon

https://www.blueletterbible.org/Comm/spurgeon_charles/sermons/0983.cfm