Stacey was educated at Eton College and King's College, Cambridge; entry to King's was, in Stacey's time there, restricted to people educated at Eton.
[2] He remained as a Fellow of King's College until 1863, but also qualified as a lawyer, being called to the bar in 1857 and thereafter practising on the South Wales circuit.
[2] He married Theodosia, daughter of Charles Tyndall of Bristol, in 1862 and the marriage, with a subsequent legacy, made him extremely wealthy.
[2] Stacey's wealth enabled him to become a generous philanthropist and benefactor, and he put up the money and contributed to the design of the stained glass in the great west window of King's College Chapel, Cambridge in 1879, which had been left plain when the chapel's other stained-glass windows were constructed in the 16th century.
[5] The article states that Stacey felt especial remorse over an incident in which, in advance of his own marriage, he bequeathed his town "girl-friend" to another King's Fellow, named Ridler – Fellows of King's College were expected to be celibate – but that Ridler had subsequently died in the girl-friend's bed; Stacey had been involved in a subterfuge which saw the dead Ridler returned to King's, where the body was "discovered" the following morning dead in his own bed.