He played significant roles in the Charity Organisation Society (COS) and the Metropolitan Association for Befriending Young Servants (MABYS), and as an ally of the settlement movement in London.

[1] His financial circumstances—namely the possession of a private income, allowing him to take on some clerical positions without hardship—then soon changed, something attributed by the Oxford Dictionary of National Biography to a drop in prices for West Indian sugar.

[14] Moving to the Greenwich vicarage in 1880, Lambert played a full part in charity and educational organisation in the large parish for nearly 20 years.

Lambert spoke on the other side of the question, suggesting that a reasonable pension proposal, such as Booth's five shilling a week figure, would take up an idea backed by much public opinion, and could put the issue out of reach of the socialist left.

It also proved a catalyst for the settlement movement, based on ideas already raised in discussions by Lambert, with Samuel Augustus Barnett and others.

It included also his Brasenose contemporary John Oakley and Harry Jones (1823–1900);[22] with sympathisers F. D. Maurice, Andrew Kennedy Hutchison Boyd and Phillips Brooks.

[25][26] Thomas Hughes named Lambert and Harry Jones, with Maurice, Stanley and others, in an 1878 list of "theological liberals" in the generally conservative Church of England.

[27] In campaigning for free education in south-east London, during the 1880s, Lambert encountered much conservative opposition; an ally was Russell Wakefield, then at Sydenham.

[28] Lambert was one of a small number of Church of England priests who worked in the most deprived areas of London, in the third quarter of the 19th century—before the social issues reached a peak of attention.

[30] John Ruskin met in 1867 with the layman Edward Denison, Green, then at St Philip's, Stepney, and Lambert, to discuss "what could be done for the poor.

"[31] Lambert's take on a settlement or colony to help Denison's plan was for men to move in, become rate payers, and so strengthen the local boards which were his particular concern.

[33] In 1876 Kate Potter, assisting Octavia Hill, met Lambert and Annie Townsend, secretary of MABYS, while collecting rents in the East End.