What is the "Analogy of Faith"?

My good friend Steve Owen wrote in answer to this question:

The Analogy of Faith is a Scriptural concept revived at the Reformation. The expression is derived from Romans 12:6 ('kata tes analogian tes pistews'- according to the analogy of the faith). According to this principle, the Scriptures can never contradict themselves, so the exegete should study all relevant biblical passages on any one topic to avoid contradictions and achieve harmony.

Simply put - the Bible does not ever contradict itself. Therefore we must study through it to be sure we are not applying a text in a way that runs contrary to what the rest of the Bible says. We use Scripture to interpret Scripture. If a portion of Scripture is not clear, then we use other Scriptures to help us understand. As our Confession of Faith confirms:

The infallible rule for the interpretation of Scripture is the Scripture itself, and therefore whenever there is a question about the true and full sense of any scripture (which is not manifold, but one), it must be searched by other passages which speak more clearly.

The supreme judge, by which all controversies of religion are to be determined, and by which must be examined all decrees of councils, opinions of ancient writers, and doctrines of men and private spirits can be no other than the Holy Scripture, delivered by the Spirit. And in the sentence of Scripture we are to rest, for it is in Scripture, delivered by the Spirit, that our faith is finally resolved.

~The Second London Baptist Confession of Faith, Chapter 1, Sections 9 & 10

~pastorway