From 1685 till his death he was principal of St Edmund's Hall; and in 1704 he was nominated by Queen Anne to a prebendal stall in Canterbury.
Andrewes was preferred to the prebendal stall of St Pancras in St Paul's, London, in 1589, and on the 6th of September of the same year became master of his own college of Pembroke, being at the time one of the chaplains of Archbishop Whitgift.
The duke of Bavaria offered to dispense with teaching, if he would only reside, and would have named him on these terms to a chair in his new university of Ingolstadt, with a salary of zoo ducats, and the reversion of one or more prebendal stalls.
In 1863 he was given a prebendal stall at St Paul's, and from 1869 to 1874 he was a member of the committee appointed by Convocation to revise the authorized version of the Old Testament.
For the energy displayed in the contest Horsley was rewarded by Lord Chancellor Thurlow with a prebendal stall at Gloucester; and in 1788 the same patron procured his promotion to the see of St David's.