While the sentiment that our lives should reflect the Gospel is absolutely accurate, the phrase’s intended meaning seems to be that sharing the Gospel verbally is sort of a last resort. It fosters a mentality of “I shouldn’t need to say anything; I just need to live it out.” But Scripture presents something else. Consider Romans 10:14-15:
“How, then, can they call on the one they have not believed in? And how can they believe in the one of whom they have not heard? And how can they hear without someone preaching to them? And how can anyone preach unless they are sent?”
The clear indication here is that words are necessary. While our lives should not contradict the words that we say, the God ordained method of spreading the Gospel is with words; and specifically words that are based on The Word.
So, I suggest a revision of this phrase. Perhaps a more accurate rendering would be “Preach the Gospel at all times, and let your life back up your proclamations.” Not as catchy, maybe, but effective nonetheless.
To God Be the Glory,
Pastor Andrew