Is witness a noun or a verb?

In the first chapter of the New Testament book of "Acts" Jesus disappeared from His followers. But, before He went away, He told them that they would receive power to be witnesses. In Christian circles we think of witness as a verb. Witnessing equates to a shared testimony about Jesus. Even though that is an accurate picture of witnessing, it is incomplete. Jesus intended for His followers to understand that witness has to do with our existence, not just our words. In order to be witnesses of Jesus we must think in terms of how we reflect and represent His identity. Every day and everywhere we are witnesses. Some days we are good and faithful witnesses. At other times we do not reflect the true character and identity of Jesus. Either we reveal Jesus to others or we damage their understanding of His character. The challenge for us is to live every moment "in Jesus name". That has caused me to examine daily actions. The verbs in my life, my actions, create the noun, my witness.