First of all, it is important to note that a true contradiction exists only when there is no possible way to reconcile two statements. If the seemingly conflicting statements address different things or employ their terminology in varying senses or if all of the facts are unknown or unclear, then it is not fair to charge a document with contradiction. A contradiction is a form of untruth. A narrative should be treated as credible unless it can be shown conclusively not to be.
Now, what are the facts relative to these two passages?
As they stand in our common Bibles, there does appear to be a discrepancy. In the first place, Jehoram, the father of Ahaziah, died at the age of forty years (2 Chron. 21:5, 20). When Jehoram died, Ahazaiah ascended to the throne (2 Chron. 22:2). If the son was forty-two years old at the time, then he was two years older than his deceased father! Clearly, then, there is a problem with the numeral “forty-two” in this passage, as such appears in our standard texts.
How is the matter to be resolved? Two solutions have been proffered by respectable scholars.
One solution offered is that the Hebrew text of 2 Chronicles 22:2 literally describes Ahaziah as a “son of forty-two years.” Some scholars have argued that this phrase does not mean that he as an individual was forty-two years old when he came to the throne. Rather, they suggest that the expression depicts the sum of years that had passed since the founding of the dynasty of Omri, the father of Ahab (note the phrase “house of Ahab” v. 3), from whom Ahaziah was descended through his mother (v. 2b).
From the time of Omri, to that of Ahaziah, was some forty-two years. You might read Lightfoot’s explanation as cited in Adam Clarke’s Commentary (at 2 Kings 8:26). See also John W. Haley’s, Alleged Discrepancies of the Bible (p. 398), Robert Jamieson in the Jamieson, Fausette, & Brown Bible Commentary (Vol. I, p. 546), and in the Seventh-day Adventist Bible Commentary (Vol. 3, p. 269).
Another solution most scholars believe is that the text in 2 Chronicles reflects a scribal error. There is some evidence for the belief that the ancient Hebrews did not spell out numbers, as is the case in modern texts. Rather, there was a letter-number system by which numbers were signified by letters of the Hebrew alphabet—though how far back this practice goes is speculation (cf. John Davis, Biblical Numerology, Baker, 1968, p. 38).
Several of the letters in the Hebrew script are strikingly similar in appearance, and such is the case with the letters which represent twenty-two and forty-two. A very slight stroke of the pen could blur the distinction.
If it should be objected that God could have protected the scribes from any and all mistakes, one need only remind himself that such a precise oversight would have involved a miraculous influence on the scribes across the centuries. Clearly, that was not Jehovah’s plan for the exercise of miraculous phenomena. For an excellent discussion of scribal transmission, see Haley (Discrepancies, p. 19ff).
In addition, several ancient translations cast doubt upon the forty-two figure. Most manuscripts of the Septuagint have the number twenty, and one has twenty-two. Twenty-two is also reflected in the Syriac and the Arabic versions. Accordingly, some of the more current English translations have changed forty-two in 2 Chronicles 22:2 to twenty-two (NASB, NIV, ESV).