True practical Christianity (never let it be forgotten) consists in devoting the heart and life to God ; in being supremely and habitually governed by a desire to know, and a disposition to fulfil his will, and in endeavouring under the influence of these motives to " live to his glory." Where these essential requisites are wanting, however amiable the character may be, however creditable and respectable among men ; yet, as it possesses not the grand distinguishing essence, it must not be complimented with the name of Christianity. This however, when the external decorums of Religion are not violated, must commonly be a matter between God and a man's own conscience; and we ought never to forget, how strongly we are enjoined to be candid and liberal in judging of the motives of others, while we are strict in scrutinizing, and severe in questioning, our own. And this strict scrutiny is no where more necessary, because there is no where more room for the operation of self-deceit.
William Wilberforce, A Practical View of the Prevailing Religious System of Professed Christians : in the higher & middle classes in the country, contrasted with real Christianity. T. Cadell (London: 1829) 214-215.