There he became a Doctor of Canon Law, in 1383 or earlier, put together an index to the fourth book of the Decretals of Gregory IX (Repertorium quarti libri decretalium), wrote a commentary to the Regulae juris (Longleat, MS 35, fols.
All the monastery's income from, for example, its oblations and manors thus passed through his office, with him allocating a sufficient allowance to meet the expenditure of each obedientary (e.g. cellarer, sacrist).
With this financial control, within a year of election Chillenden had restarted the rebuilding of the nave (paused since Simon Sudbury's murder in 1381).
This occurred both in urban areas like Southwark, London (where it bought houses and shops previously belonging to a Robert Little, and built new ones) and Canterbury (creating new buildings in Burgate and Stourstreet, along with a huge new inn called The Chequers, and purchasing a new inn called The Crown), in the priory's rural manors (with new granaries, stables, fulling mills, watermills and barns being built, often with roof tiles, rare at this period), and in the priory itself (with the chapter house restored, a new 903 lb silver-gilt table-altar purchased, and the prior's chapel and residence - among other buildings - extensively improved).
He represented both Christ Church Priory and the English crown at the 1409 Council of Pisa, though five years earlier [1405] he had refused to accept the role of bishop of Rochester, to which he had been elected.