大毘盧遮那成佛經疏 10.108

10.108

釋迦是百福德義。以因中曾百度修福，所謂一百遍作大無遮施會普施眾生，故得成此勝生。以初釋字為種子，因以為名也。是止息義，止息諸障。障既息已增益其福，迦羅是增進也。又奢（入）即是奢摩他也。常以深言利益諸天，故心為真言。亦佛化生也。

Śakra has the meaning of a hundred merits. Because on the causal ground he cultivated merit a hundred times—namely, holding a great unhindered donation assembly one hundred times to universally give to sentient beings—he was able to achieve this supreme birth. Taking the initial syllable *śa* as the bīja, he was named accordingly. It has the meaning of cessation: pacifying all obstacles. Once obstacles are pacified, his merit increases; *kāra* is advancement. Furthermore, *śa* is śamatha. Constantly benefiting the devas with profound words, his heart is therefore made into the mantra. He is also an emanation of the Buddha.