2 Corinthians 11:6
I may not be a trained speaker, but I do have knowledge. We have made this perfectly clear to you in every way.
1 Peter 4:11
If anyone speaks, he should do it as one speaking the very words of God. If anyone serves, he should do it with the strength God provides, so that in all things God may be praised through Jesus Christ. To him be the glory and the power for ever and ever. Amen.
Philippians 1:14
Because of my chains, most of the brothers in the Lord have been encouraged to speak the word of God more courageously and fearlessly.
1 Peter 3:15-16
15. But in your hearts set apart 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,
16. keeping a clear conscience, so that those who speak maliciously against your good behavior in Christ may be ashamed of their slander.
1 Thessalonians 2:4
On the contrary, we speak as men approved by God to be entrusted with the gospel. We are not trying to please men but God, who tests our hearts.
2 Corinthians 13:2-3
2. I already gave you a warning when I was with you the second time. I now repeat it while absent: On my return I will not spare those who sinned earlier or any of the others,
3. since you are demanding proof that Christ is speaking through me. He is not weak in dealing with you, but is powerful among you.