觀無量壽佛經疏 1.43

1.43

答曰：「論中稱佛，唯欲自成佛果。經中稱佛，為簡異九十五種外道。然外道之中，都無稱佛之人。但使稱佛一口，即在佛道中攝，故言已竟。」

Answer: 'In the treatise, calling upon the Buddha is done solely with the desire to achieve the Buddha-fruit for oneself. In the sūtra, calling upon the Buddha is meant to distinguish them from the ninety-five kinds of non-Buddhists. Among non-Buddhists, there is no one who calls upon the Buddha. But if one even utters the Buddha's name once with one's mouth, one is already subsumed within the Buddha path; therefore it says "already completed."'