William Jay, The Christian Contemplated in a Course of Lectures

"God works by means; and it is by his people that he principally carries on his cause in the world. They are his witnesses. They are his servants. He first makes them the subjects of his grace, and then the mediums. He first turns them from rebels into friends, and then employs them to go and beseech others to be reconciled unto God. For they know the wretchedness of a state of alienation from him. They know the blessedness of a return. They have "tasted that the Lord is gracious." Their own experience gives them earnestness and confidence in saying to those around them, "O taste, and see that the Lord is good: blessed is the man that trusteth in him."