As Mongol: If you place Relics in your Prayer Tent and have the Tithe Barns research (can also be the enhanced version) and spam pack/unpack of the building the resource income will tick each time for unlimited resources.
Trying to do it as fast as possible with 5 Relics I was able to get 2000 food, 2000 wood, 750 gold and 1300 gold per minute.
See the video below: