Laudator Temporis Acti

Oxford English Dictionary (electronic edition), s.v. clergy, n., sense II.5:

'Clerkly skill'; learning, scholarship, science. Obsolete except in proverb (quot. 1699, 1822).

[....]

1699 B. E. New Dict. Canting Crew at Clerk-ship    An Ounce of Mother-Wit is worth a Pound of Clergy, or Book-learning.

1822 S. SMITH Wks. (1859) II. 3/1    The old saying, that an ounce of mother wit is worth a pound of clergy.

Cf. OED, s.v. clerisy, n., sense 1:

Learned men as a body, scholars.

a1834 S. T. Coleridge Lit. Remains (1836) I. 238    After the Revolution..a learned body, or clerisy, as such, gradually disappeared.

The date should be pushed back from 1834 to 1830. Coleridge used the word clerisy in his book On the Constitution of the Church and State, According to the Idea of Each (London: Hurst, Chance, and Co., 1830), p. 47:

The Clerisy of the nation (a far apter exponent of the thing meant, than the term which the usus et norma loquendi forces on me), the clerisy, I say, or national church, in its primary acceptation and original intention comprehended the learned of all denominations;—the sages and professors of law and jurisprudence; of medicine and physiology; of music; of military and civil architecure; of the physical sciences; with the mathematical as the common organ of the preceding; in short, all the so called liberal arts and sciences, the possession and application of which constitute the civilization of a country, as well as the Theological.

Or rather 1829, as Eric Thomson informs me. According to The Collected Works of Samuel Taylor Coleridge, Vol. 10: On the Constitution of the Church and State, ed. John Colmer (Princeton: Princeton University Press, 1976), p. xv, despite the imprint date of the first edition, the work actually appeared in December of 1829.