Two questions: What exactly is meant by this phrase? What is its source?
There may be various wordings (see below), which don’t seem to alter the meaning but might be significant as to the source.
Background: A gospel song I’ve learned recently (“If That Don’t Make You Want to Go”) has the line “Our faith will end in sight,” or alternatively “Our faith will be made sight.” My minister said it was from the Bible, but I haven’t found it yet. In googling, I found “faith will become sight,” but not as a quote from the Bible. Rather, it seems to be a popular phrase in talking about a Biblical concept (what will happen in Heaven).
The phrase is “faith will give way to sight” and it’s not from the Bible, it’s just a popular expression. It means that when we are in heaven, we won’t need faith anymore because our faith will have become a reality – i.e. we will see God.
It’s also in the last verse of the hymn “It is Well with my Soul”, or a slight variation: “Oh Lord, haste the day when our faith be made sight” (I may not have the precise wording right; it’s been a while sing I’ve sung the thing.) I’m not sure if that’s an example of usage or the origin of the phrase, though. Anybody?
I think it’s possibly in reference to 2 Corinthians 5:7, which (talking about the limitations of living in a mortal body) says “we live by faith, not by sight” - the implication (spoken of elsewhere in the chapter) being that when mortal life ends, believers will live by sight, not faith - that is, they’ll see God firsthand and faith will not be required any longer.
For now we see through a glass, darkly; but then face to face: now I know in part; but then shall I know even as also I am known.1 Cor 13:12 KJV
The christian life in this world requires faith (as in Now faith is being sure of what we hope for and certain of what we do not see.Heb 11.1.) In the life to come, the truth will be visible, so faith now is replaced by sight in the hereafter. This sort of imagery is consistent through the New Testament, but is not expressed in the words of the OP - which may have been drawn from the hymn (and there are other hymns with the same imagery if not the words).