In Matthew 3 John the Baptist is baptizing people and then prophesies to the Jews who came to watch. One of the things he says is:
And now also the axe is laid unto the root of the trees: therefore every tree which bringeth not forth good fruit is hewn down, and cast into the fire. (Matthew 3:10)He then prophesies that Christ's mission is about to begin and he has so much more to offer than he, John, can offer them. Soon after that John baptizes Jesus (in the same chapter) and Jesus' mission begins.
Then, a few chapters later, we read the contents of Jesus' sermon on the mount. At one point, he explains how there are two paths. One is narrow, while one is broad or wide. Few people find the narrow gate and path. On the other hand, there are many on the wide road. He then continues to discuss false prophets and how we can recognize them. (False prophets lead people down the wide path.) He then says,
16 Ye shall know them by their fruits. Do men gather grapes of thorns, or figs of thistles? 17 Even so every good tree bringeth forth good fruit; but a corrupt tree bringeth forth evil fruit. 18 A good tree cannot bring forth evil fruit, neither can a corrupt tree bring forth good fruit. 19 Every tree that bringeth not forth good fruit is hewn down, and cast into the fire. 20 Wherefore by their fruits ye shall know them. (Matthew 7)We can know false prophets by the fact that they do not bring forth good fruit. Then, he says, every tree that does not bring forth good fruit is cut down and burned. Sound familiar? John said earlier that the axe was laid at the tree.
Jesus then continues, referring back to the path leading to heaven.
21 ¶Not every one that saith unto me, Lord, Lord, shall enter into the kingdom of heaven; but he that doeth the will of my Father which is in heaven. 22 Many will say to me in that day, Lord, Lord, have we not prophesied in thy name? and in thy name have cast out devils? and in thy name done many wonderful works? 23 And then will I profess unto them, I never knew you: depart from me, ye that work iniquity. (Matthew 7)So, staying on the narrow path involves doing the will of the Father. Not doing the will of the Father means we are not on the narrow path. Then, Jesus continues to say that when judgment day rolls around there will be many who will have done some pretty amazing things, including prophesying and casting out devils, but Jesus will say, "I never knew you!"
For a long time I thought that spiritual gifts were the fruit. But, Jesus is clearly saying that spiritual gifts are not the fruit. Knowing Christ is the fruit!
What does it mean to know Christ? A verse in Doctrine and Covenants 93:1 comes to mind:
Verily, thus saith the Lord: It shall come to pass that every soul who forsaketh his sins and cometh unto me, and calleth on my name, and obeyeth my voice, and keepeth my commandments, shall see my face and know that I am;This verse describes the essence of knowing Christ: Seeing his face and interacting with him as one person would with another. Until then, we might have faith, even sure faith, but we don't have knowledge of Christ yet. Without seeing Christ in the flesh, we lack fruit. The majority of people think they possess the fruit, but in reality do not. Having spiritual experiences, receiving communications from the Holy Ghost, possessing and using spiritual gifts are all important, but they are not the fruit. These are like the leaves. There are signs of life and there is the potential for fruit, but until we see Christ, we do not yet possess fruit.
Whether one sees Christ or not is a sign of the purity of their heart. Christ said in the Sermon on the Mount: "Blessed are the pure in heart: for they shall see God" (Matthew 5:8). Those who have pure hearts will see God, while those who have impure hearts will not. If we want to see Christ, we need to begin with purifying our hearts.
At the end of Jesus' mission he returns to Jerusalem. The end is in sight and he will be crucified soon. He then sees a fruitless fig tree and curses it so that it dies.
And when he saw a fig tree in the way, he came to it, and found nothing thereon, but leaves only, and said unto it, Let no fruit grow on thee henceforward for ever. And presently the fig tree withered away. (Matthew 21:19)He then goes on to teach his disciples about the faith necessary to do remarkable things, such as cursing a fig tree. But, why would he use the killing of a tree to teach that? What is the significance of the timing of this miracle? Why was the tree fruitless? How does this relate to John the Baptist's prophecy?
Jesus had preached to the Jews. He had taught them the necessity of changing their hearts and not just complying with outward ordinances. He tried to overthrow the commandments of men and focus on the commandments of God. Despite all this, they rejected him and who he was. Some saw him as a blasphemer. Others viewed him as someone who could overthrow the Roman rule. Regardless, the majority reminded blind. They did not come to know Jesus even though he himself was teaching them and performing miracles among them. They did not purify their hearts.
In essence, this nation was like a tree without fruit. John the Baptist had prophesied that they would be a fruitless tree, despite Jesus' ministry. And his prophesy came true. In my mind, Jesus cursing the tree was a sign representing the fulfillment of the prophesy. Eventually, in 70AD, Jerusalem was destroyed. Destruction comes to fruitless trees.
We are living during the time of times of the Gentiles. Again, the axe is laid at the root of the tree. Prophecies have been made that the Gentiles will not accept Christ and his teachings.
28 And when the times of the Gentiles is come in, a light shall break forth among them that sit in darkness, and it shall be the fulness of my gospel; 29 But they receive it not; for they perceive not the light, and they turn their hearts from me because of the precepts of men. 30 And in that generation shall the times of the Gentiles be fulfilled. (Doctrine and Covenants 45)As you continue to read section 45 it describes some of the destruction that will come as a result of being a fruitless tree and rejecting truth and not purifying one's heart. If we want possibly to be spared the destruction, we are required to accept truth and purify our hearts. Follow the Spirit in all things. He will lead us to Christ. He will lead us to possessing fruit, which only comes through the true vine (see John 15).