I could be trite and say, “Yes, because the Bible says so.” However, I want to come at this question from another perspective. While the proposed answer wouldn’t be wrong, practically we need to seriously consider whether we believe that the words in the Bible are for our benefit.

Sure, we can speak in the abstract all day, but do we really believe that Number 26 is a chapter that we should read?After all, it is a census of the new generation entering the land of promise. How spiritually upbuilding can that be? At the risk of being called a Fundamentalist nut-job (which probably wouldn’t be the first time!) I am going to explain why we should read every page of the Bible. Someone implied that reading levitical law codes and censuses from the OT would be ridiculous. Here is my attempt to reply:

1) Genealogies in the OT benefit the Christian by showing its historical reliability. Rather, as people are shown to be in a line of descendants, their historical veracity is secured.
2) Related to the above: Unlike other religious books, stories in the Bible are not based in some ambiguous setting. If you read the Bhagavad Gita, you will see that there is no solid grounding in years and historical figures. However, we know that in the year that King Uzziah died (~739 BC) Isaiah saw the Lord. King Uzziah was a real man who lived in our physical world.
3) “Boring” genealogies also strengthen the fact that the accounts are not embellishments of reality. Sure, there are certain genres of biblical literature that seem grandiose (i.e. apocalyptic), but this does not preclude their truthfulness.
4) Levitical laws should be read privately and publicly. HOWEVER, I understand my reader’s sensitivity to this. When they are read, they must never be pulled from their immediate context. Nor should they be read without history in mind. The Christian reads the OT through the lens of Jesus fulfilling the law and the prophets. Leviticus is a very devotional book that has been relegated, too many times, to “I don’t need to read that! I live in the 21st century under the New Covenant.” While the latter is true, the former implication is not. Actually it heightens the necessity of reading the OT! In order to understand where you are, you need to know where others have been. What’s more, in order to understand the magnificence of Christ accomplished on our behalf, we must know what he fulfilled in his life. Thus, reading about clean/unclean laws should humble us that we do not live in such a time. Instead of crying out, “Unclean! Unclean!” in the streets and being forsaken by our family, Christ was forsaken (Mt 27.46) and he was made sin for us (2Cor 5.21). The beauty of the work of Christ on behalf of God-haters is magnified in light of the OT requirements.