A. W. Pink on Assurance
Here is A.W. Pink quote that has blessed me and I pray blesses you as well brothers and sisters:
“First, the very fact that you are conscious of these sins and are so much concerned over your failure to overcome them, is a healthy sign. It is the blind who cannot see; it is the dead who feel not—true alike naturally and spiritually. Only they who have been quickened into newness of life are capable of real sorrow for sin. Moreover, such experiences as we have mentioned above evidence a spiritual growth: a growth in the knowledge of self. As the wise man tells us, "he that increaseth knowledge increaseth sorrow" (Eccl. 1:18). In God’s light we see light (Ps. 36:9). The more the Holy Spirit reveals to me the high claims of God’s holiness, the more I discover how far short I come of meeting them. Let the midday sun shine into a darkened room, and dust and dirt which before were invisible are now plainly seen. So with the Christian: the more the light of God enters his heart, the more he discovers the spiritual filth which dwells there. Beloved brother, or sister, it is not that you are becoming more sinful, but that God is now giving you a clearer and fuller sight of your sinfulness. Praise Him for it, for the eyes of the vast majority of your fellows (religionists included) are blind, and cannot see what so distresses you!
Second, side by side with sin in your heart is grace. There is a new and holy nature within the Christian as well as the old and unholy one. Grace is active within you, as well as sin. The new nature is influencing your conduct as well as the old. Why is it that you so desire to be conformed to the image of Christ, to trust Him fully, love Him fervently, and serve Him diligently? These longings proceed not from the flesh. No, my distressed brother or sister, sin is not your complete master; if it were, all aspirations, prayers, and strivings after holiness would be banished from your heart. There are "as it were the company of two armies" (Song of Sol. 6:13) fighting to gain control of the Christian. As it was with our mother Rebekah—"the children struggled together within her" (Gen. 25:22)—so it is with us. But the very "struggle" shows that the issue is not yet decided: had sin conquered, the soul would no longer be able to resist. The conqueror disarms his enemy so that he can no longer fight back. The very fact that you are still "fighting" proves that sin has not vanquished you! It may seem to you that it soon will: but the issue is not in doubt—Christ will yet save you from the very presence of sin.”
You can read this and more here gospel assurance for very cheap ($1.99) here:
Studies on Saving Faith: https://a.co/d/3muqVvN