Therefore, my beloved brethren, be steadfast, immovable, always abounding in the work of the Lord, knowing that your labor is not in vain in the Lord. – 1 Corinthians 15:58

There are great blessings connected with patient endurance…Christian workers, you must work for results, for, though conversion is the work of God, it is in many cases as clearly a product of the holy living, the devout teaching, and the fervent praying of His servants, as anything can be the result from a cause! Go on, go on, and may you have real conversions; not pretended conversions; not such as are sometimes chronicled in newspapers—“Fifty-one conversions of an evening”—as if anybody knew! May there be real conversions, and ripe fruits for Jesus in the growth and advance of those who are converted and may many of them turn out to be such fruit-bearing Christians when they are matured in grace, that the richest result in the prosperity of the church may come to you from all your work!

In this world, look not for a reward; you may have a grateful acknowledgment in the peace, and quiet and contentment of your own spirit, but do not expect even that from your fellow men! The pure motive of any man who serves his generation well is generally misrepresented; as a rule, the lounger looks on at the laborer not to praise, but to blame him, not to cheer him, but to chide him. The less he does, the less he will be open to rebuke, and the more he does, oftentimes, and the more vigorously, the more he shall be upbraided! Look not for your reward here. Suppose men praise you; what is their praise worth? It would not fill your nostrils if you were about to die! The approval of those who have neither skill nor taste; what pleasure can it afford the artist? Should one stoop for it, or, having it, lift his head the higher? Our reward is the approval of God, which He will give of His abundant grace. ~ C.H. Spurgeon

https://www.blueletterbible.org/comm/spurgeon_charles/sermons/1025.cfm