Below is an extract from Bavinck's Prolegomena that sums up the story of liberal theology:
"Form and content are never so mechanically and externally related that a total change in one will leave the other unaltered. The conversion of religious 'representations' into philosophical 'concepts' also affects the religious content itself. The history of Hegelian thought soon brought this reality to light. In it virtually nothing remained of the Christian dogma; 'Trinity,' 'incarnation,' 'satisfaction,' though retaining their orthodox names, were interpreted very differently. The facts of Christianity were regarded as its form and considered worthless. In their place came concepts that no longer had any content."
Herman Bavinck, Reformed Dogmatics vol. 1 Prolegomena, p. 257