Read this link:
https://faithalone.org/journal/1997ii/Wilkin.html
"Dr. R. C. Sproul is a very articulate spokesman for the view that assurance is not certainty. A few years back he described his own struggles with assurance, and in so doing he explained his view of assurance:
There are people in this world who are not saved, but who are convinced that they are. The presence of such people causes genuine Christians to doubt their salvation. After all, we wonder, suppose I am in that category? Suppose I am mistaken about my salvation and am really going to hell? How can I know that I am a real Christian?
A while back I had one of those moments of acute self-awareness that we have from time to time, and suddenly the question hit me: "R.C., what if you are not one of the redeemed? What if your destiny is not heaven after all, but hell?" Let me tell you that I was flooded in my body with a chill that went from my head to the bottom of my spine. I was terrified.
I tried to grab hold of myself. I thought, "Well, it's a good sign that I'm worried about this. Only true Christians really care about salvation." But then I began to take stock of my life, and I looked at my performance. My sins came pouring into my mind, and the more I looked at myself, the worse I felt. I thought, "Maybe it's really true. Maybe I'm not saved after all."
I went to my room and began to read the Bible. On my knees I said, "Well, here I am. I can't point to my obedience. There's nothing I can offer. I can only rely on Your atonement for my sins. I can only throw myself on Your mercy." Even then I knew that some people only flee to the Cross to escape hell, not out of a real turning to God. I could not be sure about my own heart and motivation. Then I remembered John 6:68. Jesus had been giving out hard teaching, and many of His former followers had left Him. When He asked Peter if he was also going to leave, Peter said, "Where else can I go? Only You have the words of eternal life." In other words, Peter was also uncomfortable, but he realized that being uncomfortable with Jesus was better than any other option!
According to this way of thinking, certainty is not an option. The very best option available is "being uncomfortable with Jesus.""
And also, Dr Belcher:
"Dr. Richard Belcher, author of
A Layman's Guide to the Lordship Controversy,2 spoke a few years ago on a Dallas radio talk show. I called in and asked a few questions about assurance. The following is a transcript of my questions and his answers:
BW: Is it possible for any Christian to have 100% certainty that they are saved and that they can't lose it if the quality of my lifestyle has something to do with my assurance? In other words, can I be absolutely sure that I'm saved?
RB: Well, the question is, can anyone have 150% definite, positive you know [assurance].
BW: Right, that's my question.
RB: Well, my question is, can even the one who is walking with the Lord and knows the Lord and is submitted to the Lord and is full of God's Spirit [have such absolute certainty]?--He will have
an assurance but that is not to say that there will never be any questions of doubt. But the Spirit of God overcomes the questions of doubt and grants assurance. See, what you're doing is putting assurance in the category of percentages and I don't like to do that.
BW: Are you 100% completely sure that you are going to Heaven?
RB: I have
an assurance that I am saved, but I am still in this body and I am human and in the passing of time there can be some questions in one's mind, but the Spirit of God witnesses to my spirit that I'm saved.
BW: Is it possible that you're not saved?
RB: Well, there are various means whereby I look at my life to see if I give evidence of salvation. Not only the witness of the Holy Spirit, but there are other means whereby I look to see if I'm saved, like Paul says in 2 Corinthians 13: "Examine yourselves whether you're in the faith." And I seek to do that as well as the witness and testimony of the Holy Spirit.
If good works are indispensable for assurance as Belcher believes, then certainty is indeed impossible. No matter how godly one is today, he is not, as Belcher acknowledges, perfect: "I am still in the body and I am human." We are left with assurance that includes doubts."
And also John Calvin:
“We cannot imagine any certainty that is not tinged with doubt, or any assurance that is not assailed by some anxiety. . . . Believers are in perpetual conflict with their own unbelief” (Calvin,
Institutes, 3.2.18).
I agree with Sproul, Belcher, and Calvin.