Ancitanirdeśa sūtra is the foundation (pioneer) of the Lotus Sutra (Saddharmapundarīka Sūtra). In this sutra, the Buddha told the Great Dignity Bodhisattva: ”There is a practice that can help sentient beings quickly attain supreme enlightenment. This method of practice, developed from the understanding of formlessness' (animitta), is also called 'immeasurable meaning'. Thus, we should practice this Sutra of Immeasurable Meaning (Anatanirdeśa)-the profound and supreme sutra of the Mahayana.Tzu Chi established their practices based on the Anatanirdeśasūtra. The Venerable Cheng Yen emphasizes that ”Tzu Chi's practice of Buddhism starts from the gate of wholesomeness,” and ”Humanism means a model of morality, and a good culture that lasts throughout history.” Thus, in this article, I will try to briefly outline the Chinese version of the Anatanirdeśasūtra, then discuss the theme of the sutra-'the practice of formlessness.' Next, I will talk about Tzu Chi's ideology and aspirations on humanism. Finally, based on the Ten Virtues mentioned in the Amitarthasutra, I will analyze Tzu Chi's practice of humanism, how they try to follow the teachings on 'formlessness,' and go in depth into the learning of Buddhism through the practice of wholesomeness, and hence, realize the model of morality.