Born in Grantham, the son of Thomas Hascard and Alice Hand, Hascard married Rachel Fane on 4 February 1667, at Gray's Inn Chapel, Middlesex.
He was buried in St Giles’s Church, Stoke Poges, where a monument was erected in his memory.
Hascard was educated at Emmanuel College, Cambridge, where he was awarded a BA in 1661, an MA in 1664, and a DD in 1671. Thereafter he held clerical appointments in plurality, as Rector of St Michael Queenhithe (1669–1671), Rector of Brickhill Bow, Buckinghamshire (1669–1671), Prebendary of Salisbury (1671–1708), Chaplain to the King (1677–1708), Rector of St Clement Danes (1678–1708), Rector of Bishops Stoke, and Rector of Great Haseley (1697–1708). He was appointed to the third stall in St George's Chapel, Windsor Castle in 1671, a position he held until 1684, when he was appointed Dean of Windsor.
Hascard was the author of three published religious works:
- A discourse about the charge of novelty upon the reformed Church of England: made by the papists asking of us the question, where was our religion before Luther? (London : T. Basset and A. Swalle, 1685)
- A sermon preached before the ... lord mayor ... at the parish-church of St. Botolph, Aldgate (London : Walter Kettilby, 1685)
- A short examination of a discourse concerning edification, by Dr. Hascard, in a letter (London : A. Baldwin, 1700)
- Fasti Wyndesorienses, May 1950. S.L. Ollard. Published by the Dean and Canons of St George's Chapel, Windsor Castle
- Views of the Most Interesting Collegiate and Parochial Churches in Great Britain by John Preston Neale and John Le Keux (London: Longman, Hurst, Rees, Orme, Brown and Green, 1824).