Hi Mpendulo, great question. This is actually something that I have written on before, so I have included that article below.

There are a lot of people searching for errors and contradictions in the Bible to prove it is not inspired by God. If it tells a single lie, then it’s not true because God cannot lie by definition, as the argument goes. One of these alleged contradictions is the one you found: the parallel accounts of 2 Kings and 2 Chronicles. In 2 Kings 24:8, it states that, “Jehoiachin was eighteen years old when he became king.” However, in 2 Chronicles 36:9, it says that he was only, “eight years old when he became king.” (KJV, NKJV) How then, can this discrepancy be explained?

The fact is, that the Bible we currently possess is a copy (and a translation) of the original autographs. This is because the originals were “written on perishable materials, and had to be copied and recopied for hundreds of years before the invention of the printing press….”[1] This is also true for other ancient documents. It is highly significant, though, that unlike other documents from antiquity, “the Bible has more manuscript evidence to support it than any ten pieces of classical literature combined.”[2] Despite the fact that the copyists took great care in duplicating the originals, some mistakes and slips of the pen were inevitably made. Nevertheless, a mistake in the copy of the book isn’t the same as a mistake in the original manuscript. And that’s why the doctrine of Biblical inerrancy applies only to the original autographs. Does this bring into question the reliability of our current copy of the Bible? Absolutely not. Why? Because, in comparing our modern copy to the recently discovered but much older Dead Sea Scroll manuscripts, scholars found “that the Hebrew manuscripts on which our OT translations are based were well preserved and carefully copied through the centuries, for they bear close resemblance to the OT manuscripts….”[3] Also very important to note is that no well-attested variation in the recovered manuscript copies alter any doctrine of the Bible whatsoever. The variations are mostly in the spelling of proper names and in numbers as we see in the present example.[4][5]

So then, regarding the age discrepancy of Jehoiachin, eminent Old Testament scholar Gleason Archer concludes, “Obviously there has been a textual error committed by the copyist either in 2 Kings or in 2 Chronicles. This type of error occurs now and then because of blurring or surface damage in the earlier manuscript from which the copy is made. A numerical system generally in use during the fifth century (when Chronicles was probably composed—very likely under Ezra’s supervision) features a horizontal stroke ending in a hook at its right end as the sign for ‘ten’; two of them would make the number ‘twenty.’ …The digits under ten would be indicated by rows of little vertical strokes, generally in groups of three. Thus what was originally written as a horizontal hooked stroke over one or more of these groups of short vertical strokes (in this case, eight strokes) would appear as a mere ‘eight’ instead of ‘eighteen.’  [Therefore,] [t]he probabilities are that 2 Chronicles 36:9 is incorrect, both because the age of eight is unusually young to assume governmental leadership—though Joash ben Ahaziah was only seven when he began to reign (2 Kings 11:21) and Josiah was only eight (2 Kings 22:1)—and because the Chaldeans treated him as a responsible adult and condemned him to permanent imprisonment in Babylon after he surrendered to them in 597 BC. Moreover, it is far less likely that the copyist would have mistakenly seen an extra ten stroke that was not present in his original than that he would have failed to observe one that had been smudged out.”[6]

Lastly, all commentaries I’ve read state that the Kings manuscripts unanimously have Jehoiachin as 18-years-old when he became king (his reign was only 3 months long, after all), whereas the Chronicles manuscripts appear divided between 8 or 18. This further supports that it was, in fact, a scribal error.

Whatever be the case, this discrepancy, like all the other minor scribal slips, obviously does not affect or change any Biblical doctrine whatsoever. And we can be confident that there was no mistake in the original manuscripts breathed out by God Himself (2 Timothy 3:16).

Thanks so much for writing in Mpendulo. Hope this helps! God bless.