觀無量壽佛經義疏 3.65

3.65

「『見此事者，即見十方一切諸佛。以見諸佛，故名念佛三昧。』」見多佛者，法身體同，念佛三昧從此得名。二、觀佛身。

"[The Buddha said:] 'One who sees this sees all the Buddhas of the ten directions. Because one sees all Buddhas, it is called the buddhānusmṛti-samādhi.'" Seeing many Buddhas is because their Dharma-bodies share the same essence; the buddhānusmṛti-samādhi derives its name from this. Second, contemplating the Buddha's body.