Van Mildert was now Chaplain to the Worshipful Company of Grocers and Rector of St Mary-le-Bow. Although situated in the London Diocese, Bow was a peculiar of Canterbury, making Van Mildert's diocesan not Beilby Porteus but again Archbishop Moore. The benefice was an influential one whose rich historical associations Van Mildert savoured.

Bow was a popular venue for charity sermons and anniversary meetings: in 1802 the SPCK held its Annual Service at Bow instead of St Paul's Cathedral to protest against the replacement of ‘the usual verses of the 113th Psalm’ by an anthem. It was also the traditional home of a number of memorial sermons and lectures, most notably the series endowed by Robert Boyle in 1692.

A long-standing wrangle over one of these lectureships gave Van Mildert the chance to establish himself with the Archbishop. The terms of this particular endowment required twelve respectable parishioners to appoint ‘some honest Godly zealous & learned Preacher’ to read ‘a Lecture or Sermon’ on one afternoon each week. This led to power-struggles between Rector and lay electors: the Rector had no control over the choice of preacher, but could ban anyone he disapproved from his pulpit. In 1774 the Rector, Dr Sclater, did just that when he lost the election to the Revd Thomas Clarke, and commenced delivering the lectures himself. The parishioners sued, filing an Information in Chancery in 1776. Sclater's death saved the immediate situation, but left the legal position unclear.