In a large bowl, combine oats, flour, 1 cup brown sugar, salt and baking soda. Fold in butter until mixture becomes crumbly. Press half of the mixture into the bottom of a 9x9-inch baking pan.

In a small saucepan, combine dates, water and 1/3 cup brown sugar, and bring to a boil on medium heat setting. Cook until thickened.

Stir in lemon juice and remove from heat. Spread over the oatmeal base, and spread the remaining crumb mixture on top of this.

Bake for 25 minutes in 350°F oven. Do not overcook or the topping will dry out.