'I am Jesus, the One you're hunting down like an animal. But now, up on your feet—I have a job for you. I've handpicked you to be a servant and witness to what's happened today, and to what I am going to show you.' (Acts 26:15-16)
A witness is one who has sufficient knowledge to constitute enough proof that something exists, or perhaps that someone is who they say they are, or that there is evidence to the contrary for one or the other. It may not be clear to you, but you are being spoken to by God - direct communication with God - and the message is clear! We are being "handpicked" by God to be his messenger and to act as a witness to the power of our holy and righteous God. We are called to stand on the side of God - to give a testimony to the reality of his existence - to proclaim his actions are 'spot on' in all regards. The effectiveness or what others will believe about our witness is often viewed by the kind of people that we are in our ordinary everyday lives, not what we say. All the preaching, teaching, or sharing we do is useless if what we "say" doesn't match with what we "live out" in our everyday lives. To be faithful to the message of hope that lives within us (Christ), we need the power of the constant flow of the Holy Spirit in our lives.
There is no substitute for power - we can light a candle, but it dims in comparison to the light afforded when a light bulb is connected to an outlet that feeds it the voltage to "light it up". That difference is found in the 'energy' source - one 'burns' the small wick secured within that candle wax; while the other 'burns' the energy provided by huge turbines moved by pressures exerted by wind or water. One is dim because the source of energy is less than the other. It is the same with our Christian walk - we cannot find any substitute for the power of the Holy Spirit within us. The operation of the power of the Holy Spirit will be that which produces conviction, convinces of the truth, and affords a conversion in our lives. Our own energy to 'live right' is kind of like that candle - it is dim in comparison to the energy source of the Spirit within. A witness has a personal awareness of what they share. It is the work of the Holy Spirit within to bring about this personal awareness of God.
The 'witness' within our lives comes first in conviction - bringing us to a place where we recognize our need for a Savior, moving us into a place where we are constantly aware of the sinfulness inherent within our lives apart from Christ. The witness grows as we are convinced of the truth - allowing us to see the error of our wrong choices, opening to us the truth of God's standards by which we are to pattern our lives, moving us from making wrong choices to making better ones little by little. In bringing about the conversion of our lives into that which brings honor and glory to our holy God, the Spirit of God within is helping us to become 'reliable witnesses' of the work of God's grace within us. It is the last point that makes us solid witnesses of the truth about who God is in our lives. When there is a lifestyle change, there is a witness that is linked to the grace of God.
God's work within our lives is never secretive. There is always a witness of his grace touching us - we may not display the "why" behind the grace (the sinfulness that led us to the place of needing that grace), but we definitely display the "freshness" of that grace (the hope and joy it produces in our lives)! That is the type of "witness" that God asks us to be - channels of his grace by allowing his grace to be "lived out loud" in our lives. Wherever God's grace has affected your life, let it shine out! The witness of God's grace in that area of your life may be the very hope that reaches out to another in need of that same grace in their life! Just sayin!