For I know that my Redeemer liveth… – Job 19:25

“I KNOW that my Redeemer lives.” To say, “I hope so, I trust so,” is comfortable; and there are thousands in the fold of Jesus who hardly ever get much further. But to reach the marrow of consolation you must say, “I KNOW.” Ifs, buts, and perhapses, are sure murderers of peace and comfort. Doubts are dreary things in times of sorrow. Like wasps they sting the soul! If I have any suspicion that Christ is not mine, then there is vinegar mingled with the gall of death; but if I know that Jesus is mine, then darkness is not dark; even the night is light about me. Out of the lion cometh honey; out of the eater cometh forth sweetness. “I know that my Redeemer lives.” This is a brightly burning lamp cheering the dampness of the sepulchral vault, but a feeble hope is like a flickering smoking flax, just making darkness visible, but nothing more! I would not like to die with a mere hope mingled with suspicion. I might be safe with this, but hardly happy; but oh, to go down into the river knowing that all is well, confident that as a guilty, weak, and helpless worm I have fallen into the arms of Jesus—and believing that He is able to keep that which I have committed to Him! I would have you, dear Christian friends, never look upon the full assurance of faith as a thing impossible to you. Say not, “It is too high; I cannot attain unto it.” …If Job before the coming and advent still could say, “I know,” you and I should not speak less positively! God forbid that our positiveness should be presumption; let us try ourselves, and see that our marks and evidences are right, lest we form an ungrounded hope, for nothing can be more destructive than to say, “Peace, peace, where there is no peace.” But oh, let us build for eternity, and build solidly; let us not be satisfied with the mere foundation, for it is from the upper rooms that we get the widest prospect. Let us pray the Lord to help us to pile stone on stone, until we are able to say as we look at it, “Yes, I know, I KNOW that my Redeemer lives.” This, then, for present comfort today in the prospect of departure. ~ C.H. Spurgeon

https://www.blueletterbible.org/comm/spurgeon_charles/sermons/0504.cfm