How do you go about applying a book like Numbers? There is a wrong path, of course. We might call this moralising. It's where one takes a story in the Old Testament and simply wrenches it out of context and applies it directly. An absurd example would be not cutting our hair, because, after all, that's where Samson's strength lay.
In our hearts we know this is not the right approach, so we fall back on the biblical theological approach, which Jesus himself endorses. The Emmaus Road discourse, as well as some key passages in John, remind us that, ultimately, the story of the Bible is the story of Jesus. it is all, in some way, about him and takes us to him.
But too many preachers stop there. As a result, preaching becomes dull (yes, even about Jesus!) because, effectively, that only is one thread of application, and you can't survive or grow on just one, albeit significant, line. It's interesting to read then, what the Apostle Paul says about interpreting the book of Numbers, or (at least) the wilderness wanderings.
1 For I do not want you to be ignorant of the fact, brothers and sisters, that our ancestors were all under the cloud and that they all passed through the sea. 2 They were all baptized into Moses in the cloud and in the sea. 3 They all ate the same spiritual food 4 and drank the same spiritual drink; for they drank from the spiritual rock that accompanied them, and that rock was Christ. 5 Nevertheless, God was not pleased with most of them; their bodies were scattered in the wilderness. 6 Now these things occurred as examples to keep us from setting our hearts on evil things as they did. 7 Do not be idolaters, as some of them were; as it is written: “The people sat down to eat and drink and got up to indulge in revelry.”[a] 8 We should not commit sexual immorality, as some of them did—and in one day twenty-three thousand of them died. 9 We should not test Christ,[b] as some of them did—and were killed by snakes. 10 And do not grumble, as some of them did—and were killed by the destroying angel. (1 Corinthians 10).
Spot the applications?
Do not be idolaters
Do not commit sexual immorality
Do not test the Lord
Do not grumble
So, whilst we should avoid moralising, we are naive and narrow to think that there is no exemplary role for the Old Testament. Of course, the skill of understanding it and weaving into the bigger narrative of the story of Jesus is not straightforward, but we are not being faithful to Scripture if we ignore it.