Heat the oil in a large high-sided skillet or Dutch oven over medium heat.
Add the garlic and break it up with a spatula.
Add the tomatoes and salt and stir to combine.
Cover tightly with a lid, and cook until the tomatoes have collapsed and released their juices, 3 to 5 minutes.
Stir the beans and water into the tomato mixture.
Cover and simmer until the beans are warmed through, 2 to 3 minutes.
Add the spinach to the beans a big handful at a time, stirring and allowing each addition to wilt before adding more.
Turn the heat off and add the lemon juice and pepper.
Add more salt if needed.
Serve hot.
