An objection on the power of free will.
Germanus: This passage very clearly shows the freedom of the will, where it is said “If My people would have hearkened unto Me,” and elsewhere “But My people would not hear My voice.” For when He says “If they would have heard” He shows that the decision to yield or not to yield lay in their own power. How then is it true that our salvation does not depend upon ourselves, if God Himself has given us the power either to hearken or not to hearken?
Source: Conferences (New Advent)