Maintenance for the week of March 25:
• [COMPLETE] ESO Store and Account System for maintenance – March 28, 9:00AM EDT (13:00 UTC) - 12:00PM EDT (16:00 UTC)
Hey, @ZeFeZ. Only one person needs the Pledge of Mara in order to complete the ceremony. Keep in mind that you both need an open inventory slot and to be at the proper shrine for it to take effect.
After you've used the Pledge of Mara, to activate the bonus you both need to be wearing your rings, in a group, and in the same zone.