Number One
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Brother Cavil is a priest who speaks with Chief Tyrol (Lay Down Your Burdens, Part I) after Tyrol's maddened attack against Cally. Cavil identifies the source of Tyrol's anxiety as arising from fear that he is a Cylon agent just waiting to be activated.
A somewhat eccentric figure, Cavil is rather a harsh critic of prayer for a priest, but claims to have been preaching "longer than you [Tyrol] have been sucking down oxygen."
Cavil is portrayed by Quantum Leap's Dean Stockwell.