Duane Litfin author of Word Versus Deed: Resetting the Scales to a Biblical Balance (Wheaton: Crossway, 2012), has a piece (here) in Christianity Today devoted to that topic – the balance between ‘the relative roles of words (proclaiming the gospel) and deeds (loving action) in what Christ has called his people to be and do’.
He devotes some space to the saying, wrongly attributed to Francis of Assisi – ‘Preach the gospel at all times. Use words if necessary’ – noting:
‘The belief that we can “preach the gospel” with our actions alone represents muddled thinking. However important our actions may be (and they are very important indeed), and whatever else they may be doing (they serve a range of crucial functions), they are not “preaching the gospel.” The gospel is inherently verbal, and preaching it is inherently verbal behavior. If the gospel is to be communicated at all, it must be put into words.’
Towards the ends of his piece he notes three consequences of conflating the roles of words and deeds: (1) ‘it can lead to an eclipse of our verbal witness’, (2) ‘it can deceive us into thinking the power of the gospel lies within us’, and (3) ‘it can put us out of step with God's own modus operandi in the world’.