When our faith is quickened and we are made one with God, He writes His truth on our hearts and we know the truth. This is made real for us when we study God’s Word and hear godly expositional preaching and Bible teaching. The Holy Spirit is working in our hearts to see and understand the truth. This is why we are so taken aback by the attacks against our faith. 

And on that day you will not question Me about anything. Truly, truly, I say to you, if you ask the Father for anything in My name, He will give it to you.
John 16:23 (LSB) 

In our journey these past several weeks we have looked at the nature of faith, the veracity of the Bible as the Word of God, and the deity of Christ. Much of this has been done as the result of or in response to attacks by liberals, Christian and otherwise. I often ponder what could possibly be their goal. Why should they care that we proclaim that Jesus Christ is THE WAY, THE TRUTH, and THE LIFE and no one comes to Father except through Him? When we analyze that then it becomes clear that their attacks are on the exclusivity of the genuine Gospel.

Genuine faith, the product of God’s grace (Romans 4:16; Ephesians 2:8,9) is possessed only by the regenerate. This faith is alive whereas before God’s grace quickened it, it was completely incapable and unwilling to believe in Christ as Lord and Saviour. This dead faith is inherited from Adam and the product of the fall. (Genesis 3) Without God’s grace according with man’s faith, there is no possibility of belief and, therefore, no possibility of salvation. However, when God quickens a sinner (we are all sinners) his or her faith comes alive. The spiritual blindness that marked them before regeneration is washed away.

But when the kindness and affection of God our Savior appeared, ⁵ He saved us, not by works which we did in righteousness, but according to His mercy, through the washing of regeneration and renewing by the Holy Spirit, ⁶ whom He poured out upon us richly through Jesus Christ our Savior, ⁷ so that having been justified by His grace, we would become heirs according to the hope of eternal life.
3:4-7 (LSB) 

With this cleansing and renewal of the Holy Spirit believers are made one with the Father. They have come to the Father through the Son. This faith is supernatural. It is cleansed and because of that it can see and understand spiritual truth. As Christian’s mature they will find that their spiritual walks become more and more lined up with God’s will. With this regenerated faith and the work of the Holy Spirit within them they have the ability to not sin. They can obey God. They can walk in repentance. On the other hand, before this none of this is possible because the unregenerate person’s righteousness is as filthy rags before the Lord. What is not of faith is sin. (Romans 14:23b)