Perhaps there is a nagging doubt in your heart. Assurance cannot be for me. If only you knew what I have done or struggled with, then you would understand, pastor, why I cannot have this assurance you speak of.
Well, then consider this: God knew every sin you would commit long before you committed it, even before you were born, before even the creation of the world. And still, he sent his Son to die for you, for every sin you have committed, yes, including that one that haunts and grieves you and sometimes keeps you up at night. What is more, do you really think that after all Jesus Christ did for you, suffering and dying on the cross, bearing the weight of God’s awful wrath for your sin—and that he did this even while you were still an enemy of his—do you really think that now—now that he calls us saints and even friends of his—that he will just walk away, that he will just give up on you? No! He loved you to the bitter end on the cross (John 13:1). He will love and sustain you now all the way till the end of time and greet you with these words: Well done, good and faithful servant.
Believe this, dear child of God. This, this is the gospel! This is blessed assurance!
6 And I am sure of this, that he who began a good work in you will bring it to completion at the day of Jesus Christ.