A lot of Christians think this means being nice.

Jesus said for us to go into all the world being witnesses unto Him.

If I am on trial and need a witness, I would certainly want them to speak on my behalf (not theirs). I'd like for them to tell the court about my Character (not theirs). I'd like for them to talk about my Goodness (not theirs). I'd like them to talk about my Grace (not theirs).

Don't try to be like Jesus . Talk about Him and watch the Holy Spirit manifest Him through you.

• Ezekiel 36:27
  And I will put my Spirit within you, and cause you to walk in my statutes, and ye shall keep my judgments, and do them.

• Ezekiel 37:14
  And shall put my Spirit in you, and ye shall live, and I shall place you in your own land: then shall ye know that I the LORD have spoken it, and performed it, saith the LORD .
• Romans 8:1
  There is therefore now no condemnation to them which are in Christ Jesus , who walk not after the flesh, but after the Spirit .

• Galatians 5:16
  This I say then, Walk in the Spirit , and ye shall not fulfil the lust of the flesh.

• Galatians 5:25
  If we live in the Spirit , let us also walk in the Spirit .