Harsh usage turned his thoughts from the prospects of commercial life, and at the age of sixteen he entered Glasgow College (November 1794) to study for the ministry.

Straitened means interrupted Drummond's course, and left him without a degree, but he acquired considerable classical culture, and as a very young student began to publish poetry, in which the influence of the revolutionary ideas of the period culminating in 1798 is apparent.

Leaving Glasgow in 1798 he became tutor in a family at Ravensdale, County Louth, pursuing his studies under the direction of the Armagh presbytery, with which he connected himself on the ground of its exacting a high standard of proficiency from candidates for the ministry.

He at once received calls from First Holywood and Second Belfast, and accepting the latter was ordained on 26 August 1800, the presiding minister being William Bryson [q. v.] He became popular, especially as a preacher of charity sermons, and dealt little in topics of controversy.

In 1815 he was an unsuccessful candidate for the chair of logic and belles-lettres in the Belfast Academical Institution, and on 15 October that year he was called to Strand Street, Dublin, as colleague to James Armstrong, D.D.

He was soon elected a member of the Royal Irish Academy, contributed frequently to its Transactions, held for many years the office of its librarian, and took a scholarly interest in Celtic literature.

Some years after his settlement in Dublin Drummond came out as a polemic, exhibiting in this capacity a degree of sharpness and vivacity which seemed a rather remarkable outcome of his gentle and genial temperament.

In two instances (in 1827 and 1828) he took advantage of discussions between disputants of the Roman Catholic and established churches as occasions for bringing forward arguments for unitarian views; and in the controversies thus provoked he was always ready with a reply.