Place beans in a large pot. Cover with water and stir in baking soda. Soak at room temperature for 8 to 12 hours.
Drain and rinse beans; return to the pot. Cover with water and bring to a boil over medium-high heat. Reduce heat and simmer until beans are tender yet firm to the bite, about 25 minutes. Drain beans, reserving water. Set beans and cooking water aside.
Heat olive oil in the same pot over medium heat. Sauté garlic and sage in hot oil until fragrant, about 2 minutes. Add beans; cook and stir until beans absorb the aroma of garlic and sage.
Pour in tomato sauce; bring to a simmer. Cook, stirring occasionally, until beans are soft but not mushy, 10 to 15 minutes. Add reserved cooking water to keep sauce from burning if needed. Season with salt and pepper. Serve warm.