Here are some very comforting thoughts from Rev. U. V. Koren, father of Lutheranism in Northeast Iowa and one of the founders of Luther College, Decorah:
In answsering the question, "Can and ought a Christian be certain of his salvation?" Rev Koren wrote:
"[The Christian] is to believe, i.e., he is humbly and in a childlike manner to rely upon the promises which God has given him precisely concerning [salvation]. Those promises are more firm than heaven and earth and are given just for this purpose, that we are to blieve them, have a firm conviction regarding that He will fulfill them in spite of the devil, the world and our flesh."
"Yes, indeed, God would have us believe that it is unalterably certain that we shall sometime be saved. For He has given us all these glorious words and promises that we should believe them. He has surely not given them to us that we should doubt them. "For the Son of God. . . was not yea and nay, but in him was yea. For the promises of God in him are yea, and in him Amen, unto the glory of God by us" 2 Cor. 1:19, 20.