From Final Fantasy Wiki

Chivalry is the name of an ability or set of abilities available to the Paladin job class in various games of the series.

Appearances

Final Fantasy XI

Chivalry is a merit ability for Paladins in Final Fantasy XI. It allows them to convert their TP into MP.

Final Fantasy Tactics Advance

Main article: Paladin (Final Fantasy Tactics Advance)

Chivalry is the name of the skillset used by Paladins. It consists mostly of defensive and supportive actions, but also with a couple Holy attacks.

Final Fantasy Tactics A2: Grimoire of the Rift

Main article: Paladin (Final Fantasy Tactics A2)

Chivalry is again a skillset learned by Paladins. It contains most of the same abilities as in the game's predecessor.

From the RuneScape Wiki, the wiki for all things RuneScape

Chivalry

Members only?	Yes
Level	60
Drain rate	1 point every 1.5 seconds
Effect	+20% Defence, +18% Strength and +15% Attack

The Chivalry Prayer gives a temporary 20% boost to a player's Defence skill, 18% boost to a player's Strength and 15% boost to a player's Attack. Requirements for using chivalry are completion of King's Ransom and Knight Waves Training Grounds along with 65 Defence and 60 Prayer. As with all member prayers, this cannot be used on a free-to-play server.

Trivia

• Today, the terms chivalry and chivalrous are used to describe courteous behaviour, especially that of men towards women.
• The Chivalry prayer used to be seen in a 'prayer bubble' above one players head, like protection prayers, but now it doesn't.

Requirements for using Chivalry.

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Chivalry