Rabbi Shmuel Heller came to the Bat Ayin with a difficulty in Maimonides' writings. According to tradition, his teacher asked him to return after Minchah. When he did, the Bat Ayin reviewed the passage and explained it quickly.
More than Solving the Question
Rabbi Shmuel was impressed by the quick answer. The Bat Ayin drew his attention to the effort of prayer: a properly offered Minchah requires great inner work. The story places depth of study alongside the work of prayer and shows how the tzaddik approached even the ordinary prayer of every day.
For further exploration: The Bat Ayin's Practices, Bat Ayin and Its Teachings andStories and Testimonies.