John 17:3

Jesus prayed that we would come to know Him and His Father.

3 And this is this is life eternal, that they might know thee the only true God, and Jesus Christ, whom thou hast sent.

Life eternal

The literal translation of the original Greek phrase means life that is never ending. However, there is a difference between living forever (immortality), which is guaranteed to every person who lives on earth because of the Resurrection of Jesus Christ, and eternal life, which means living forever in the presence of God. This scripture teaches that knowing God is part of eternal life. Here are some other things the scriptures teach us about eternal life:

The Atonement of Jesus Christ made it possible (see John 3:15–16).
God’s work and glory is to help us receive it (see Moses 1:39).
It will be given to those who receive the gospel and work righteousness (see D&C 20:14) and are faithful and endure (see D&C 50:5).
We should hope for it (see Moroni 7:41).
Faith, repentance, baptism, receiving the Holy Ghost, and enduring to the end qualify a person for it (see 2 Nephi 31:10–21).
It is the greatest gift of God (see D&C 14:7).

Know thee

“Seek to know your Father in Heaven. He loves you, and He has given you the precious opportunity to draw near to Him as you pray. …

“You can also come to know your Father by learning about His Beloved Son and applying the gospel in your life. …

“You draw near to God the Father as you study the scriptures and the words of latter-day prophets and as you give service. When you follow God’s will and live as He would have you live, you become more like Him and His Son. You prepare yourself to return to live in Their presence.”

True to the Faith: A Gospel Reference (2004), 75–76.

The only true God

“Some wonder, why is belief in God so important? … Without God, life would end at the grave and our mortal experiences would have no purpose. Growth and progress would be temporary, accomplishment without value, challenges without meaning. There would be no ultimate right and wrong and no moral responsibility to care for one another as fellow children of God. Indeed, without God, there would be no mortal or eternal life.”

Elder Robert D. Hales of the Quorum of the Twelve Apostles, “Seeking to Know God, Our Heavenly Father, and His Son, Jesus Christ,” Ensign, Nov. 2009, 29.

Whom thou hast sent

“God in His ultimate effort to have us know Him, sent to earth His Only Begotten and perfect Son, created in His very likeness and image.”

“In all that Jesus came to say and do, including and especially in His atoning suffering and sacrifice, He was showing us who and what God our Eternal Father is like, how completely devoted He is to His children in every age and nation. In word and in deed Jesus was trying to reveal and make personal to us the true nature of His Father, our Father in Heaven. He did this at least in part because then and now all of us need to know God more fully in order to love Him more deeply and obey Him more completely.”

Elder Jeffrey R. Holland of the Quorum of the Twelve Apostles, “The Grandeur of God,” Ensign, Nov. 2003, 71, 70.