This is a quote from John Owen regarding the presence of sin in the lives of Christians:
Sin does not only still abide in us, but is still acting, still laboring to bring forth the deeds of the flesh. When sin lets us alone we may let sin alone; but as sin is never less quiet than when it seems to be the most quiet, and its waters are for the most part deep when they are still, so ought our contrivances against it be vigorous at all times and in all conditions, even where there is least suspicion.~John Owen (Of The Mortification Of Sin In Believers, Part 1, Chapter 2)
John Owen was a puritan born in the early 1600s. This quote was taken from the book Overcoming Sin and Temptation, Three Classic Works By John Owen, published by Crossway in 2006.
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