Depending on your story’s pacing, you may decide your best choice is to have your character face and defeat his Lie for this final time before he charges into the Climax. At this moment, your character will reject the last remnants of doubt about the Lie and step forward to claim the Truth. He is, at last, completely centered—and, as a result, completely empowered to face the antagonist. He is transformed.
The Climax begins as the character acts upon his new Truth, finally and fully. By this point, the character should be finished with all lengthy internal pondering.