'A hedge,' as mentioned in Matthew 21:33, signifies preservation from falsities of evil which are from hell.

In Genesis 49:6, this signifies that from a depraved will they enfeebled the external good of charity. (Arcana Coelestia 6357)

In Genesis 49:22, this signifies to fight against falsity.

In Exodus 14:22, a wall signifies something that holds back falsities on all sides. (Arcana Coelestia 8206, 8235)

In Joel 2:9, this represents essential falsity. (Arcana Coelestia 8906[3])

In Ezekiel 13:10, 14, this signifies falsity adopted as a principle and made to appear as truth. (Apocalypse Explained 237[5])

In Ezekiel 8:10, this signifies the interior natural where man's filthy things reside. (Apocalypse Explained 650[66])

In Revelation 21:12, this signifies the Word in its literal sense, which protects the doctrine of the Lord's New Church. (Apocalypse Revealed 898)

(Odkazy: Arcana Coelestia 922)