Never leave off watching, reading, praying, and striving until you experientially find Christ Jesus formed within you. In a particular manner, my dear friend, watch against all temptations to sloth. When you receive the sacrament, earnestly endeavor to be inwardly bettered by it the week following. Live every day as holily as you can. Be frequent in self-examination morning and evening. Pray earnestly from your heart. – George Whitefield (1714-1770), in a letter dated April 2,1736.