The goal of eternal life is possible only to those who have been born again. Living in heaven is only possible if you have been born again. Jesus said,
Jesus answered, Verily, verily, I say unto thee, Except a man be born of water and of the Spirit, he cannot enter into the kingdom of God. (John 3:5)
One cannot be saved by themselves. By complying with the requirement of repentance, an individual qualifies for God to effect a change in their desires. Being washed in the Holy Spirit changes a person beyond what they can change of themselves. One group expressed it this way:
“...the Spirit of the Lord Omnipotent, which has wrought a mighty change in us, or in our hearts, that we have no more disposition to do evil, but to do good continually.” (Mosiah 5:2)
The mighty change in heart does not remove a person from the opposing temptation to do evil. Instead, it shifts the source of the disposition to do evil. Instead of coming from within, it comes from without.
The resulting purification allows increased communication with God through the Holy Spirit, enabling the individual instruction necessary to bring us to eternal life.
Being born again provides us with the confidence we need to stand in the presence of God:
14 And now behold, I ask of you, my brethren of the church, have ye spiritually been born of God? Have ye received his image in your countenances? Have ye experienced this mighty change in your hearts?
15 Do ye exercise faith in the redemption of him who created you? Do you look forward with an eye of faith, and view this mortal body raised in immortality, and this corruption raised in incorruption, to stand before God to be judged according to the deeds which have been done in the mortal body? 16 I say unto you, can you imagine to yourselves that ye hear the voice of the Lord, saying unto you, in that day: Come unto me ye blessed, for behold, your works have been the works of righteousness upon the face of the earth? (Alma 5)
Being born again is the launch pad from which we develop the ability to overcome all temptation and become sinless.