Why was Amida Buddha important in Japanese Pure Land Buddhism?

In Japanese Pure Land Buddhism, Amida Buddha (the Japanese name for Amitabha) is the central figure of devotion and the primary source of salvation. His importance stems from his role as a compassionate savior who, as the monk Dharmakara, made a series of vows to establish a Pure Land (Sukhavati) where all beings could attain enlightenment.1234

Amida is essential for the following reasons:

• The 18th Vow: This foundational promise ensures that anyone who sincerely invokes his name—a practice known as the nembutsu—will be reborn in his paradise, free from suffering, until they reach final enlightenment.312
• Reliance on "Other Power": Japanese Pure Land thinkers like Hōnen and Shinran taught that in the age of mappō (the decline of Buddhist law), humans lack the capacity to achieve salvation through their own efforts (jiriki). Instead, they must rely on Amida’s "other power" (tariki) and grace.124
• Universal Accessibility: Amida’s path is considered the "easy path," making salvation accessible to all, regardless of their ability to perform complex rituals, meditation, or good works.124