There is a very simple yet profound passage in Matthew chapter 21 describing how repentance is connected to belief. Oddly, this pertinent passage is seldom mentioned when repentance is discussed.
But what think ye?
A certain man had two sons; and he came to the first, and said, Son, go work to day in my vineyard. He answered and said, I will not: but afterward he repented, and went. And he came to the second, and said likewise. And he answered and said, I go, sir: and went not.
Whether of them twain did the will of his father?
They say unto him, The first.
Jesus saith unto them, Verily I say unto you, That the publicans and the harlots go into the kingdom of God before you. For John came unto you in the way of righteousness, and ye believed him not: but the publicans and the harlots believed him: and ye, when ye had seen it, repented not afterward, that ye might believe him. (Mat 21:28-32)
First, notice the question the Lord asks in v. 28, "But what think ye?" This is one of the relatively few instances where the Lord asks people a question. To answer one must use his logic and reason faculties to arrive at a conclusion. Thus, the Lord wants people to "THINK"! He wants them to use the mental capabilities He created in all men.
The Lord then presents a simple story of a man with two sons. He instructs both sons to go work in his vineyard. One says he won't but later repents and does; the other says he will but doesn't. Then the Lord asks another question, "Whether of them twain did the will of his father?" The crowd does not hesitate to answer, "The first." Why did they say the first? Because the son regretted his decision and changed his position or "repented. "The fruit or result of his repentance was doing what he was initially told.
The crowd of priests understand the main premise of the story: doing the will of the father. The fact that both sons initially lied is not the emphasis. It is who in the end did the will of his father. This shows us a key truth: repentance speaks of accountability to a higher authority, and it will always produce actions that comply with the commands made by that authority. Lip service is just vain talk. The first son repented and proved his repentance by doing his father's will, i. e. his "fruits of repentance." The second "talked the talk" and had all the right words but never did what his father wanted. All is clear, true repentance produces change conducive to the authority's revealed will.
Once the Lord gets his answer from the priests, He begins to make application concerning belief. He blasts them for not believing John the Baptist who came in the "way of righteousness." John's message was to "Repent..." and if they heeded his words they would have repented with contrite hearts and the fruit of their repentance would be to believe on the coming Christ whose way John was preparing. The despised "publicans and the harlots" did believe John and repented making them eligible to believe on and receive the coming Christ and go into His "kingdom of God."
The priests had plenty of chances to repent. Even after they dismissed John they saw the publicans and the harlots repent and later believe indicating they still could too, but they "repented not afterward, that [they] might believe him." (Like the first son in the story, they could have changed their minds in spite of what they initially thought or said.) Notice very carefully those last words of the Lord, "[ye] repented not afterward, that ye might believe him!" Repentance is a prerequisite of belief! One must repent before he can truly believe (Mark 1:15).
Here some of you dear readers of the more extreme edge of the "Free Grace" persuasion may cry foul, but the stubborn fact remains; evangelical repentance is a prerequisite of evangelical belief. At some point a person must, in sorrow or regret, change his heart, mind, and attitude about, God, Christ, himself, and his sin before he can exercise true saving faith. Repentance and faith are not the same. The latter is the result of the former. Notice the progression,
The simple truth is the heart is not ready or capable of truly believing until it repents first. A man must hear God's word and turn his mind to agree with the Lord before true belief in Christ is possible. All of this happens in a person's heart or soul. Except for the hearing through the ears (or seeing words with the eyes) there is no "work" or anything physical involved. A man can hear, repent, and believe on Christ without blinking an eye. Again, repentance is not a part of salvation itself. Salvation is brought about by grace through faith, but repentance is what prepares the heart to be able to exercise that faith.