A final post before I disappear for a week to Aberystwyth...
Liberalism, old and new, has features that bear more than a passing similarity to Socinianism and Pelagianism. This is noticeable in the movement away from the person and work of Christ in the gospel message, and toward the ethical demands of his teaching. To put it crudely it is the replacement of "the gospel about Jesus" with the message of Jesus. The former, of course, includes Christ's redemptive work and his teaching (he is after all Saviour and Lord, Prophet, Priest and King). The latter, however, has no real place for Christ's redemptive significance beyond the moral influence he exerts. In any this case this has become the thing of first importance in the message. Even when redemptive language is retained it has become largely redundant, ill-fitting Scriptural phrases draped over another Jesus.
Machen said it well in his classic work Christianity & Liberalism:
Here is found the most fundamental difference between liberalism and Christianity--liberalism is altogether in the imperative mood, while Christianity begins with a triumphant indicative; liberalism appeals to man's will, while Christianity announces, first, a gracious act of God.
J. Gresham Machen, Christianity & Liberalism, p. 47