Symbolism, Imagery, Allegory
Yep. We're talking about honest-to-goodness, how-did-you-get-so-much-taller-than-everyone-else giants here.
First on the docket: Og. If it weren't for Goliath, we might remember Og as the most famous giant in the Bible. Og is an Amorite king, and he makes his appearance in many books of the Bible: Numbers, Deuteronomy, Joshua, I Kings, Nehemiah, and Psalms. With an iron bed thirteen feet long and six feet wide (ahem, "nine cubits long and four cubits wide" [3:8]), Og is a huge obstacle for Israel. But that doesn't stop them. They defeat Og, proving once and for all that they shouldn't be afraid of giants:
So the Lord our God also handed over to us King Og of Bashan and all his people. We struck him down until not a single survivor was left. (3:3)
That's one big dude they just took down. And Moses sure doesn't forget it—he mentions it over and over in Deuteronomy, bringing up the defeat in five different chapters of the book. (We're guessing there was a recent political or military victory that readers would think of every time the writers mentioned it.) Looks like Moses is really trying to boost their confidence. If they can defeat Og, they can defeat anyone, right?
A Giant Problem
When it comes to conquering Canaan, it seems like a monumental task at first. This isn't just "lions, and tiger, and bears, oh my!"—it's about conquering a vast amount of land inhabited by giants who live in massive, fortified castles. Oh, and they know you're coming.
But hey, beating one lets you know you might just be able to beat them all.
Giants represent the fear that the Israelites felt when they first tried to enter the Promised Land—and failed, mind you. This time, they'll have to face that fear, and their faith in God will have to be bigger than even the biggest of all the giants.