How, then, can they call on the one they have not believed in? And how can they believe in the one of whom they have not heard? And how can they hear without someone preaching to them? And how can anyone preach unless they are sent?
Romans 10:14-15

But in your hearts revere Christ as Lord. Always be prepared to give an answer to everyone who asks you to give the reason for the hope that you have. But do this with gentleness and respect, keeping a clear conscience, so that those who speak maliciously against your good behavior in Christ may be ashamed of their slander.
1 Peter 3:15-16

…I conformed to the strictest sect of our religion, living as a Pharisee.
Acts 26:5  

“I too was convinced that I ought to do all that was possible to oppose the name of Jesus of Nazareth.”
Acts 26:9

Many a time I went from one synagogue to another to have them punished, and I tried to force them to blaspheme. I was so obsessed with persecuting them that I even hunted them down in foreign cities.
 Acts 26:11  

“About noon, King Agrippa, as I was on the road, I saw a light from heaven, brighter than the sun, blazing around me and my companions. We all fell to the ground, and I heard a voice saying to me in Aramaic, ‘Saul, Saul, why do you persecute me? It is hard for you to kick against the goads.’” “Then I asked, ‘Who are you, Lord?’” “‘I am Jesus, whom you are persecuting,’” the Lord replied.
 Acts 26:13-15

First to those in Damascus, then to those in Jerusalem and in all Judea, and then to the Gentiles, I preached that they should repent and turn to God and demonstrate their repentance by their deeds.
Acts 26:20  

But God has helped me to this very day; so I stand here and testify to small and great alike.
Acts 26:22  

When a Samaritan woman came to draw water, Jesus said to her, “Will you give me a drink?”
John 4:7 

My message and my preaching were not with wise and persuasive words, but with a demonstration of the Spirit’s power, so that your faith might not rest on human wisdom, but on God’s power.
1 Corinthians 2:4-5

For though I am free from all, I have made myself a servant to all, that I might win more of them. To the Jews I became as a Jew, in order to win Jews. To those under the law I became as one under the law (though not being myself under the law) that I might win those under the law. To those outside the law I became as one outside the law (not being outside the law of God but under the law of Christ) that I might win those outside the law.
1 Corinthians 9:19-21 

On hearing this, Jesus said, “It is not the healthy who need a doctor, but the sick.”
Matthew 9:12  

“I planted, Apollos watered, but God gave the growth.”
1 Corinthians 3:6

Impress them on your children. Talk about them when you sit at home and when you walk along the road, when you lie down and when you get up.
Deuteronomy 6:7  

So shall my word be that goes out from my mouth; it shall not return to me empty, but it shall accomplish that which I purpose, and shall succeed in the thing for which I sent it.
Isaiah 55:11 

Your people will be my people and your God my God.
Ruth 1:16