Complex sentence: The name "A Call to Action" was adopted from he Tablet's original header to the letter, which elicited many enthusiastic responses from lay people, religious and priests, although there was also opposition from orthodox Catholics.
Split into simpler sentences: The name "A Call to Action" was adopted from The Tablet's original header to the letter. While this elicited enthusiastic responses from some lay people, religious and priests, there was also opposition from orthodox Catholics.