1 Peter 3:16 in the King James Version
Having a good conscience; that, whereas they speak evil of you, as of evildoers, they may be ashamed that falsely accuse your good conversation in Christ.
Context
15 But sanctify the Lord God in your hearts. Always be ready to give an answer to everyone who asks you a reason concerning the hope that is in you, with humility and fear,
16 having a good conscience. Thus, while you are spoken against as evildoers, they may be disappointed who curse your good way of life in Christ.
17 For it is better, if it is God’s will, that you suffer for doing what is right than for doing evil.