Under the influence of Seneca he became a keen student of philosophy and rhetoric, and began practising as an advocate.
He studied law at Princeton, New Jersey, in the office of Richard Stockton, whose sister Hannah he married in 1762, and in November 1760 he was licensed as a counsellor and attorney-at-law, afterwards practising at Elizabethtown, New Jersey.
After practising for a short time as a lawyer in the church courts, he was ordained priest, becoming rector of St Michael's church, Trongate, Glasgow, in 1465.
On the 1st of February 1773 he received information from Cairo that Abul-Dhahab had made himself Sheik al-Balad, and in that capacity was practising unheard-of extortions, which were making Egypt with one voice call for the return of All Bey.
As regards the jus vetus, therefore, the judges and practitioners of Justinian's time had two terrible difficulties to contend with - first, the bulk of the law, which made it impossible for any one to be sure that he possessed anything like the whole of the authorities bearing on the point in question, so that he was always liable to find his opponent quoting against him some authority for which he could not be prepared; and, secondly, the uncertainty of the law, there being a great many important points on which differing opinions of equal legal validity might be cited, so that the practising counsel could not advise, nor the judge decide, with any confidence that he was right, or that a superior court would uphold his view.