John R. W. Stott, The Preacher's Portrait, Some New Testament Word Studies (Grand Rapids: Wm. B. Eerdmans Publ. Co., 1961), p. 120
We must heed the memorable words written by Robert Murray McCheyne to the Rev. Dan Edwards on 2 October 1840 after his ordination as a missionary to the Jews: &ls;I trust you will have a pleasant and profitable time in Germany. I know you will apply hard to German; but do not forget the culture of the inner man,&md;I mean of the heart. How diligently the cavalry officer keeps his sabre clean and sharp; every stain he rubs off with the greatest care. Remember you are God's sword,&md;His instrument,&md;I trust a chosen vessel unto Him to bear His name. In great measure, according to the purity and perfections of the instrument, will be the success. It is not great talents God blesses so much as great likeness to Jesus. A holy minister is an awful weapon in the hand of God.'