” Synods can be heretical; only ecumenical synods are infallible (and even then, the pope must assert that nature.)”
I can’t seem to find this in the Scriptures... Or any writings before 100 bc... Or in Jesus’ words... Or in any example in Acts... Or in any Command... Or in any contemporaneous secular writings... Or Contemporaneous Sacred art...
I can only conclude it’s totally made up.
There was no need at all to call the Synod of the family. The only reason it was called was for Pope Francis to float his liberal ideas.