Be a true witness; preach the true doctrine.

1 Timothy 1:15
It is a true saying, in which all may put their faith, that Christ Jesus came into the world to give salvation to sinners, of whom I am the chief:
1 Timothy 1:16
But for this reason I was given mercy, so that in me, the chief of sinners, Jesus Christ might make clear all his mercy, as an example to those who in the future would have faith in him to eternal life.

Witnessing of Jesus who had died, but is alive

Instead, they had several arguments with him about their own religion and about a certain Jesus who had died but whom Paul kept claiming was alive.
Acts 25:19

1)Rev 1:18 And I was dead, and see, I am living for ever, and I have the keys of death and of Hell.

References
1Rev 1:18 And I was dead, and see, I am living for ever, and I have the keys of death and of Hell.

Your testimony; To witness of Jesus Christ in your life

I am a Jew of Tarsus in Cilicia by birth, but I had my education in this town at the feet of Gamaliel, being trained in the keeping of every detail of the law of our fathers; given up to the cause of God with all my heart, as you are today.
Acts 22:3

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