Gall signifies the same thing as wormwood -- that is, infernal falsity.

(Odkazy: Apocalypse Revealed 410)

In Genesis 31:42, this signifies that the Divine in the Lord united the Divine to the Human by His own power. (Arcana Coelestia 4182)

In Revelation 3:19, this signifies temptation in relation to falsities, or denials and confirmations against divine truth. (Apocalypse Revealed 215)