Howell was born about 1664 at Deptford and received his education at Lewisham Grammar School, where he was a foundation scholar, and Jesus College, Cambridge, where he graduated BA in 1684 and MA in 1688.

In the list of nonjurors at the end of Kettlewell's Life it is stated that Howell was at the Revolution master of the school at Epping, and curate of Estwich, Suffolk, but there is no such parish in that county, and Eastwick, Hertfordshire, may be meant.

[a] He composed the speech which William Paul, a nonjuring clergyman, who was convicted of taking part in the rebellion, delivered at his execution on 13 July 1716.

A prosecution was first instituted against Redmayne, the printer, who was sentenced to pay a fine of 500l., to be imprisoned for five years, and to find security for his good behaviour for life.

On his hotly protesting against the last indignity on the ground that he was a clergyman, the court answered that he was a disgrace to his cloth, and that his ordination by the so-called bishop of Thetford was illegal.