There is considerable disagreement among epistemologists concerning what the relevant sort of justification here consists in. Internalists about justification think that whether a belief is justified depends wholly on states in some sense internal to the subject. According to one common such sense of “internal”, only those features of a subject’s experience which are directly or introspectively available count as “internal”—call this “access internalism”. According to another, only intrinsic states of the subject are “internal”—call this “state internalism”. See Feldman & Conee 2001 for the distinction.
Modern Christian churches tend to be much more concerned with how humanity can be saved from a universal condition of sin and death than the question of how both Jews and Gentiles can be in God's family. According to both Catholic and Protestant doctrine, salvation comes by Jesus' substitutionary death and resurrection . The Catholic Church teaches that salvation does not occur without faithfulness on the part of Christians; converts must live in accordance with principles of love and ordinarily must be baptized.   Martin Luther taught that baptism was necessary for salvation, but modern Lutherans and other Protestants tend to teach that salvation is a gift that comes to an individual by God's grace , sometimes defined as "unmerited favor", even apart from baptism.