English: The Church has some of the best brasses in Sussex, mostly belonging to the Gage Family.

The chapel has 3 altar tombs of similar design. Sir John Gage and wife are represented by detailed alabaster recumbent effigies, and the others have brasses on the top slabs. They were designed and executed by Garat Johnson. Bartholomew Bolney (d. 1476) was Lord of the Manor of West Firle and his daughter Agnes married William Gage in 1472. He was son of Sir John Gage who married Eleanor St Clere, and had considerable lands in Sussex. They lived at the Manor of Heighton St Clere in Firle Park. Thus the two manors were joined. William and Agnes had one son, Sir John Gage, whose effigy is seen in the Chapel, along with his wife Phillipa, (daughter of Sir Richard Guildford or Guldeford. They had eight children, including Edward Gage. Sir John was Knight of the Garter, a courtier and represented Sussex in Parliament, as well as holding many important offices under Henry VIII and Mary. Sir Edward Gage (1521-1568), whose tomb chest is in the north east corner of the chapel, was High Sheriff of Sussex and Surrey under Mary I, who made him Knight of the Bath at her accession. He had the task of burning the Lewes Martyrs in 1555-1557. He married Elizabeth Parker (daughter of John Parker) about 1536, and later Joan Sackville. He had 14 children, including John, Thomas and George. John Gage (1538-1592) married Elizabeth Littleton, and Margaret Copley, and was responsible for erecting the tombs, with his own being in the north west corner of the chapel. Thomas Gage (1541-1590) married Elizabeth Guildford (Daughter of Sir Thomas Guildford, great grandson of Sir Richard mentioned earlier). They had 3 children, one son and 2 daughters who can be seen on the brass. George Gage was born about 1544, and died 1569. An inscription on the brass states: "What of the body of life? They are but a flower, a dust, a shadow that fleeth away". Half the inscription plate is missing.

Most of the coats of Arms of the families mentioned are on the tombs.