". . .that ye may know that ye have eternal life, and that ye may believe on the name of the Son of God." (1 John 5:13)

Although this powerful, five-chapter letter from the apostle John is full of vital insights into the Christian life, it is written to "little children" (1 John 5:21) so that they might "know" the majesty and wonder of eternal life.

John begins his epistle with a reminder that he "knew" this Jesus from whom the promise of eternal life came (1 John 1:1-3). John was an eyewitness to Christ's resurrection (John 20), which is the most powerful proof of the claims and promises of the Lord (Acts 17:31).

Much of that which is applied in John's epistle is based on the precise teachings of the Lord Jesus Himself, heard by John and recorded in John's gospel under the inspiration of the Holy Spirit (John 20:31).

Those who believe will "not perish" (John 3:15-16).
The "water" of Christ springs up to "everlasting life" (John 4:14).
Whoever has everlasting life "is passed" from death to life (John 5:24).
Those who come to Christ will "never hunger" (John 6:35).
No one is able to "pluck" the believer out of the Father's hand (John 10:28-30).
"Whosoever liveth and believeth in me shall never die" (John 11:26).

Based on the Word of God, John gives us several experiential tests by which we can know that we "live":

We love and keep His commandments (1 John 2:3).
We know and love the truth (1 John 2:20).
We love the brethren (1 John 3:14).
We have God's Holy Spirit (1 John 4:13). HMM III