Rev Renwick was educated at the West Herrington Council School, and the Ralph Richardson Grammar School, Ryhope. When he left school he became an Associate of Kings College, London, in 1936, and in 1942 gained his Bachelor of Divinity - however, he did not enter teaching until fifteen years later.

He attended Kings College, Newcastle, to gain his Diploma of Education, which he got in July, 1957, and he joined the staff of the South Shields Grammar-Technical School for Boys in September, 1957, as Head of the RI Department.

But his appointment was short-lived. For reasons not disclosed, his appointment was terminated by the governors within a matter of weeks.