Boston Cardinal Sean O'Malley issued a statement Thursday following comments from Pope Francis endorsing same-sex civil unions.

Those comments caused a firestorm, thrilling progressives and alarming conservatives, given official Vatican teaching prohibits any such endorsement of homosexual unions.

"The Pope's endorsement of civil unions is not an endorsement of homosexual activity," O'Malley said in his statement.

Questions were swirling Thursday about the origins of Pope Francis’ bombshell comments endorsing same-sex civil unions.