1 John 5:11–13

John writes so that those who believe may know they have eternal life

11And this is the testimony, that God gave us eternal life, and this life is in his Son.

12Whoever has the Son has life; whoever does not have the Son of God does not have life.

13I have written these things to you so that you may know that you have eternal life, you who believe in the name of the Son of God.

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9If we receive the testimony of people, the testimony of God is greater, because this is the testimony of God, that he has testified about his Son.

10Whoever believes in the Son of God has the testimony in himself. Whoever does not believe God has made him a liar, because he has not believed in the testimony that God has testified about his Son.

…

14And this is the confidence that we have toward him: that if we ask anything according to his will, he hears us.

15And if we know that he hears us in whatever we ask, we know that we have the requests that we have asked of him.

Read all of 1 John 5

Its words in the original

Death and Eternal Life