[2] Owing to the death of his father he left school early, and engaged for some years in commercial pursuits; but in 1830 he entered Pembroke College, Oxford, where he had Francis Jeune, subsequently Bishop of Peterborough, as his tutor, and formed a lifelong friendship with John Jackson, afterwards Bishop of Lincoln and then of London.

He took an honorary fourth class in 1884, graduating Oxford Master of Arts (MA Oxon) in 1838 and Doctor of Divinity (DD) in 1869.

[3] In 1834, he was ordained to the curacy of Wool and Lulworth, on the south coast of Dorset, and in the next year accepted a temporary engagement as chaplain to the English residents at Rotterdam.

In 1865, he was appointed by Robert Rolfe, 1st Baron Cranworth, Lord Chancellor to the well-endowed living of Tydd St. Mary, in the Fens of Lincolnshire, near Wisbech.

[2] On the appointment of James Jeremie as Dean of Lincoln in 1864, Mackenzie succeeded him as subdean and canon residentiary, and on the death of George Wilkins in 1866 was appointed to succeed him as Archdeacon of Nottingham,[5] exchanging the lucrative living of Tydd for the poorly endowed rectory of St John the Baptist's Church, Collingham, near Newark, in order that he might become resident within his archdeaconry.

But, careful never to overstep his subordinate relations to his diocesan, Mackenzie maintained the office with true dignity, and secured for it general respect.