Is there a contradiction between 2 Samuel 24:9 and 1 Chronicles 21:5, when the number of soldiers Joab counts comes up different?

The Bible does contain a number of apparent contradictions. Believing in the inspiration and inerrancy of the Word of God we know that all of these can be reconciled. It may be that a complete explanation will not come until heaven. For example, think of the Old Testament saint, who read in one text that the Messiah would suffer (Isaiah 53:1-6), but in another that He would triumph over His enemies (Psalm 2:7-9). Only in the light of our Lord’s first coming (and His teaching concerning His return) can we understand that which puzzled Old Testament saints, even prophets (1 Peter 1:10-11).

I found this comment in the Grace Theological Journal.

The Student’s Commentary on the Holy Scriptures. By George Williams. Kregel, reprinted 1971. 1058 pp. $11.95.

The reader quickly senses that this commentary is not a duplication or rehash of several other works. It is fresh, spiritual and inspiring. The devotional flavor is refreshing. Williams knew the Scriptures and he knew Him of whom the Scriptures speak. Kregel is to be commended for republishing this commentary which first appeared in 1926. George Williams was an outstanding Christian of the 19th century. He knew seven languages including Hebrew and Greek. He held high the inspiration, authority and purity of the Scriptures. He could see Christ all through the Bible. In fact, he labeled his introduction to the Psalms, “The Psalms and the Messiah.” He expounded on typology, e.g. the Red Sea and the Jordan River as types of the death and resurrection of Christ. He tackled problems such as the conflict on the numbering of fighting men between the accounts of 2 Samuel 24:9 and 1 Chronicles 21:5. He resolves the conflict by stating that the 1,100,000 soldiers of the 1 Chronicle passage included 300,000 young men not counted as “valiant” with the 800,000 soldiers of the 2 Samuel passage. He wrote about the rapture, an anti-christ and the millennium. However, his eschatology does not have the precision in dispensational lines of the 20th century.

There is also a classic book entitled, “The Mysterious Numbers of the HebrewKings” (Kregel, 1995 - on Amazon.com for 13.99) that probably addresses this issue.

Got this from the Bible Knowledge Commentary:

The figures in 1 Chronicles are 1,100,000 men in Israel and 470,000 in Judah, but the chronicler wrote that the Levites and Benjamites were not included (1 Chron. 21:5-6). The reconciliation of the data may lie in the possibility that 1,100,000 describes the grand total for Israel including the standing army which consisted of 12 units of 24,000 men each (288,000, 1 Chron. 27:1-15) plus 12,000 especially attached to Jerusalem and the chariot cities (2 Chron. 1:14). These 300,000 subtracted from 1,100,000 would yield the 800,000 figure in 2 Samuel 24:9. Also the chronicler may not have included the 30,000-man standing army of Judah (6:1) whereas they were included in chapter 24. This would raise the 470,000 total of Chronicles to the 500,000 of Samuel. This is only one solution, but with so little information available as to how the sums were obtained nothing further can be said with certainty.

Let me make a couple of comments and suggestions about the way you are approaching this fellow. First, it is great that you are seeking to witness to this fellow. Second, trying to understand and witness to a Muslim is a real challenge. Third, it seems to me that he has successfully been putting you on the defensive. My experience is that no one has ever been argued into the kingdom. When you answer each question, he may very well reject your response, and even if you win, he will simply move to the next item on his long list of “errors” or “contradictions.” You may wish to attempt to reverse this. You may want to ask him some questions about the Koran, and about his beliefs and practices. Point out the flaws in his system. Fourth, we need to pray that the Holy Spirit would convict and convince your friend of the truth. You may point out to this fellow that unless God draws him, he will not understand or accept the good news of the Gospel (1 Corinthians 2:14-16; John 6:44, 65). I would especially point out John 16:7-11. It is not your job to convince your friend of the truth, but simply to declare it. It is the Holy Spirit who convinces and convicts. In the past I have said something like this to one who is a skeptic, “Look, the Bible claims to be the true and infallible Word of God, but I cannot convince you of this; that is the job of the Holy Spirit. If what I am saying is true, then if God has chosen to save you His Spirit will convince you of the truth from within. I would encourage you to try to forget what I’ve said. But if I am right, his Spirit won’t allow you to forget it, and you will know inside that what God says about your sin and your need for a Savior is true.”

Finally, those that debate the Bible’s accuracy in this manner succeed in keeping you engaged in debate over numerical reckonings; I would insist on staying in the New Testament, and on the person and work of our Lord.