Absolute Certainty and Heaven

A question I have heard a few times over the years is this: "Are you absolutely sure that you will go to heaven when you die?" Following the speaking of the Bible's gospel message of salvation by Christ Jesus, the intention has usually been a very good one. I am 46 years old today. I was saved by God when I was 10 years old. I believe in Heaven and have assurance that I will be there in fullness of life because of Jesus' work and by the grace of God (by His stripes we are healed!). In earlier years, the notion of absolute certainty may have had a draw but now the conviction comes from a deeper and wider perspective than "absolute certainty." What does it mean to be certain of something? I am absolutely certain, perhaps, that the sun came up this morning, but I am not absolutely certain that the sun will come up tomorrow morning. God's promise of Heaven and Heaven's reality are today more convincing than the notion that the sun will come up tomorrow. And if you are absolutely sure of something, doesn't faith become unnecessary? But it is by faith we are saved such that no one can boast.