The KJV (New Testament) is based on the Greek Textus Receptus, which was Erasmus' Greek Bible. Erasmus was a contemporary of Luther and Zwigli. He went to one library and found six (I think) greek manuscripts. From these he formed the Textus Receptus, or Received Text.
Prior to this Christians did not look to the Greek, but rather the Latin text of the Roman Church.
Some people feel that more modern translations are closer to the original, because they are based on earlier manuscripts. The real problem has more to do with the philosophy of translation than the text in question, as there is little difference in ANY of the Greek texts.
What almost everyone needs to understand is that ALL translations are commentary. There are hard phrases to interpret and each translator brings his theological baggage to the table.
There are a couple of places where the NIV (as an example) replaces the Word of God with what the translators THINK God really meant.
One such place is 1 Sam 13:1. The Hebrew is so difficult to understand that the NIV translators pulled information from Acts (I think), to correct God. The text in the NIV has absolutley nothing to do with the Hebrew in 1 Sam 13:1. Following are quotes from different versions.
1 Samuel 13:1 (KJV) Saul reigned one year; and when he had reigned two years over Israel, . . .
1Sam 13:1 (NAS) "Saul was forty years old when he began to reign, and he reigned thirty- two years over Israel."
1Sam 13:1 (NIV) "Saul was [thirty] years old when he became king, and he reigned over Israel [forty-]two years."
Tyndale (Matthews' Bible): "Saul was as a child of a year old, when he began to reign. And when he had reigned two years over Israel, . . .
Geneva: "Saul now had beene King one yeere, and hee reigned two yeeres over Israel."
Young's Literal: "A son of a year [is] Saul in his reigning, yea, two years he hath reigned over Israel, . . . "
Jewish Publication Society Tanakh: "Saul was . . . years old when he became king, and he reigned over Israel two years." (Footnote: "The number is lacking in the Heb. text; also, the precise context of the 'two years' is uncertain. The verse is lacking in the Septuagint.")
The question then is it more God-honoring to assume that the text offers an acceptable meaning as it stands in the Hebrew, or to intervene with notes about what is allegedly missing?
The Massorites never made a change in this verse, due to their high respect for Scripture. I believe we can learn from their example.
John