Paley’s Evidences is one of the very best summaries of the historical case for Christianity, making good use of the work of his great predecessors Lardner and Douglas. In Part I, which is the heart of the book, Paley sets out to establish two propositions:

  1. That there is satisfactory evidence that many professing to be original witnesses of the Christian miracles passed their lives in labours, dangers, and sufferings, voluntarily undergone in attestation of the accounts which they delivered, and solely in consequence of their belief of those accounts; and that they also submitted, from the same motives, to new rules of conduct, and
  2. That there is not satisfactory evidence that persons professing to be original witnesses of other miracles, in their nature as certain as these are, have ever acted in the same manner, in attestation of the accounts which they delivered, and properly in consequence of their belief of those accounts.

In Part II he considers auxiliary evidences such as prophecy, the character of Christ, and the propagation of Christianity. In Part III he considers some popular objections to Christianity.

The edition linked to here has notes by Richard Whately, which makes it even more valuable.