Preheat the oven to 350 degrees.
Line two baking sheets with parchment paper or silicone mats.
In a mixing bowl, whisk together the flour and baking soda. Set aside.
In the bowl of a mixer fitted with a paddle attachment, cream together the butter and sugars until light and fluffy, about two minutes.
Add the eggs one at a time, mixing until each is incorporated.
Add in the vanilla and the cinnamon and mix briefly.
Add the flour mixture to the butter and sugar blend. Mix until incorporated. Be sure to scrape the sides and bottom of the bowl with a spatula.
Beat in the oatmeal in two separate additions.
Scrape the bottom and sides to be sure everything is combined.
Mix in the raisins using either a large spoon or, gently, with the mixer.
Using a cookie scoop, drop the dough onto the prepared trays leaving approximately two inches between each. You can use a tablespoon if you don't have a scoop.
Bake until golden, about 11 minutes. I generally bake two trays at a time, reversing them midway through baking (i.e, the top tray to the bottom, the bottom to the top).