When it comes to the Scriptures, textual criticism is the effort to get to the original words that were written by the original writers. It is usually something that we can leave to the super Greek studs because most of the textual differences are very minor and make no fundamental difference to the meaning of the passage. It is, however, good to pay attention to matters of textual criticism because occasionally they do bear on our interpretation of that passage. We have a good example in John 8.38.
- “I speak of what I have seen with my Father, and you do what you have heard from your father.”” (John 8:38, ESV)
- “I declare what I have seen in the Father’s presence; as for you, you should do what you have heard from the Father.”” (John 8:38, NRSV)
Notice the difference between the ESV and the NRSV. Did Jesus say “your father” or “the Father”? In short order Jesus will tell his opponents that their father is the Devil, so it is a crucial difference in understanding. Why do we not know what Jesus was referring to here?
There is an important little pronoun that was either in the original text or was added later. It is the pronoun ὑμῶν (your). As the NET Bible points out, depending upon whether ὑμῶν was in the text or not, the meaning of the passage diverges quite a bit.
‘If the pronoun is read, then the devil is in view and the text should be translated as “you are practicing the things you have heard from your father.” If it is not read, then the same Father mentioned in the first part of the verse is in view. In this case, ποιεῖτε should be taken as an imperative: “you [must] practice the things you have heard from the Father.”'(NET Notes)
When scholars get to a difficulty like this they consider all the manuscript evidence and then make a judgment call. Sometimes they agree, sometimes they do not agree. In this case most English versions think that ὑμῶν was part of the original manuscript, so they translate it as a reference to the Devil (ESV, NIV, NLT, NASB, LSG (French Version)) The translators of the NRSV went with the variant reading and so understand it as a reference to God the Father.
Who is correct? Search me. The important point is that, while the meaning of the verse changes depending upon whether ὑμῶν was part of the original text or not, it does not change our doctrinal understanding of God or the Devil one iota. The point is still true, regardless of how the passage is translated, that God was the Father of Jesus and is the Father of all who believe in Jesus, and that Jesus points out that the Devil is the father of his opponents!