In a mixing bowl, cream butter and sugar until light and fluffy.
In another bowl, combine flour, salt, and soda; add to the creamed mixture, stirring until well blended. Stir in rolled oats and chopped peanuts. Press half of the crumb mixture into the bottom of a buttered 13x9x2-inch baking pan. Spread with jelly; sprinkle with remaining crumb mixture. Bake at 400° for 25 minutes.