Richard Hooker, Of the Laws of Ecclesiastical Polity, Book 5 (1597), ch. 7, §3. Ruskin 's quotation is slightly inaccurate. In Keble's edition of 1836, which Ruskin knew, the original text reads:
To the best and wisest, while they live, the world is continually a froward opposite, a curious observer of their defects and imperfections; their virtues it afterwards as much admireth. And for this cause many times that which most deserveth approbation would hardly be able to find favour, if they which propose it were not content to profess themselves therein scholars and followers of the ancient. For the world will not endure to hear that we are wiser than any have been which went before. ( Hooker, Works, II, 41)
At the time of writing the Preface to the second edition of Modern Painters I (1844), Ruskin was reading Hooker in preparation for the writing of Modern Painters II. (See The influence of Hooker on Ruskin.) Hooker is addressing the theme described in the running head as 'Prejudice in Favour of Antiquity: why now abated'. The quotation is particularly apposite given Ruskin's evangelising, theocentric argument concerning the superiority of Turner over the old masters (see Ruskin and religion).