I originally found this quote in the Appendix to Daniel Steele’s The Gospel of the Comforter. (It is the first part of Note H.) Horace Bushnell was a Congregationalist pastor and theologian, who was quite important — and controversial — in his day. See: Wikipedia, Christian Classics Ethereal Library.
Many a time nothing is wanting but to speak as to a soul already hungry and thirsty, or, if not consciously so, ready to hunger and thirst, as soon as the bread and water of life are presented. If the problem is to get souls under sin inspired again, which it certainly is, then it is required that the preacher shall drop lecturing on religion and preach it, testify it, prophesy it, speak to faith as being in faith, bring inspiration as being inspired, and so become the vehicle, in his own person, of the power he will communicate; that he may truly beget in the gospel such as will be saved by it. No man is a preacher because he has something like or about a gospel in his head. He really preaches only when his person is the living embodiment, the inspired organ of the gospel; in that manner no mere human power, but the demonstration of a Christly and divine power. Such preaching has had, in former times, effects so remarkable. At present we are almost all under the power, more or less, of the age in which we live. Infected with naturalism ourselves and having hearers, that are so, we can hardly find what account to make of our barrenness.
— Horace Bushnell, Nature and the Supernatural: As Together Constituting the One System of God (1858).