Certainty is an unrealistic and unattainable ideal

If you're sincerely seeking God, God will make His existence evident to you.

In order to receive forgiveness, we need to place our trust in Christ as our Savior and the Lord of our lives. But if we reject Christ, then we reject God's mercy and fall back on His justice. And you know where you stand there. If we reject Jesus' offer of forgiveness, then there is simply is no one else to pay the penalty for your sin-except yourself.

Scepticism, ironically, draws its life's blood from claims to have a good deal of knowledge. For example, your friends claim to know, 'Since every possible option has not been explored, nothing can be said for certain.' That statement is itself a claim to knowledge!

But the Bible says that the unreached will be judged on a quite different basis than those who have heard the gospel. God will judge the unreached on the basis of their response to His self-revelation in nature and conscience. The Bible says that from the created order alone, all persons can know that a Creator God exists and that God has implanted His moral law in the hearts of all persons so that they are held morally accountable to God (Rom. 1.20; 2.14-15). The Bible promises salvation to anyone who responds affirmatively to this self-revelation of God

Should a conflict arise between the witness of the Holy Spirit to the fundamental truth of the Christian faith and beliefs based on argument and evidence, then it is the former which must take precedence over the latter.

The point is this: If God does not exist, then life is objectively meaningless; but man cannot live consistently and happily knowing that life is meaningless; so in order to be happy he pretends life has meaning. But this is, of course, entirely inconsistent—for without God, man and the universe are without any real significance.