"Because it has come to be so" is the only, but to him sufficient, answer which the Englishman gives for his institutions and the authority which is immanent in them.
Source, in full
Speech to the Leicester Junior Chamber (16 May 1980), quoted in Roger Scruton, 'The Language of Enoch Powell', in Lord Howard of Rising (ed.), Enoch at 100: A Re-evaluation of the Life, Politics and Philosophy of Enoch Powell (2012), p. 121