Game concept
Faith Hostility
The game also links it as Tolerance, Tolerate, Tolerates.
From the game's encyclopedia
All Faiths and Rites have a relation towards each other that is determined by how closely related they are.
Closeness is decided by several factors, such as if they share Religion, Religious Family, or if the Faith has special Doctrines.
If two Faiths are far apart, they are often able to Holy War each other.
The following relations exist: righteous, astray, hostile, and evil.
The game's text for patch 1.20.1.2. Words in blue are entries of the encyclopedia: hover one to read it, as in the game.
Faith Hostility is an entry of Crusader Kings III's in-game encyclopedia. The game explains it: "All Faiths and Rites have a relation towards each other that is determined by how closely related they are." It covers Hostile, Astray, Righteous and Evil. The game also links it as Tolerance, Tolerate and Tolerates. Patch 1.20.1.2, from game/common/game_concepts/00_game_concepts.txt and game/localization/english/game_concepts_l_english.yml.
Source: game/common/game_concepts/00_game_concepts.txt, game/localization/english/game_concepts_l_english.yml and the English localisation, Crusader Kings III 1.20.1.2.