“Doubtings, fears, and temptations, if not ordinarily prevailing, are consistent with gospel assurance. Though the devil’s power is
limited in reference to the saints, yet his hands are not tied; though he cannot prevail against them, yet he can assault them. And although there is not “an evil heart of unbelief in believers yet there will still be unbelief in their hearts. Such an evidence, conviction, and persuasion of acceptance with God as excludes all contrary reasonings, that allows the soul to hear nothing of objections, that frees and quiets it from all assaults, is neither mentioned in the Scripture, nor is consistent with that state wherein we walk before God, nor is it possible on account of Satan’s will and ability to tempt, or on account of our own remaining unbelief.

Assurance encourages us in our conflict, it does not deliver us
from it. We may have peace with God when we have none from the assaults of Satan.

Evangelical assurance is not incapable of variation. It may be higher or lower, greater or less, obscure or more evident. God sometimes marvellously raises the souls of His saints with some close and near approaches to them; gives them a sense of His eternal love, a taste of the embraces of His Son and the inhabitation of His Spirit, without the least intervening disturbance; then this is their assurance. But this life is not a season to be always taking wages in;
our work is not yet done; we are not always to abide in this mount;
we must go down again into the battle, fight again, cry again, complain again. Has the soul now lost its assurance? Not at all. It had assurance before with joy, triumph and exultation; it has assurance now, or may have it, with wrestling, cries, tears and supplications. And a man’s assurance may be as good and as true when he lies on the earth with a sense of sin, as when he is carried up to the third heaven with a sense of love and a foretaste of glory. Briefly, this assurance of salvation is such a gracious, evangelical persuasion of acceptance with God, in Christ, and of an interest in the promises of preservation to the end, wrought in believers by the Holy Ghost, in and through the exercise of faith, as for the most part produces delight in obedience, and casts out fear giving the soul a
hope and expectation of “the glory that shall be revealed” and it will even enable them to die for Christ!

From an exposition of Psalm 130

by John Owen