E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Weak-kneed Christian or Politician (A).
Irresolute; not thorough; a Laodicean, neither hot nor cold.
If any weak-kneed Churchman, now hesitating between his [political] party and his Church, is trying to persuade himself that no mischief is in the air, let him take warning.Newspaper paragraph, October 16th, 1885.