觀無量壽佛經疏 2.30

2.30

三、從收執父王下，至一不得往已來，正明父王為子幽禁。此明闍世取提婆之惡計，頓捨父子之情，非直失於罔極之恩，逆響因茲滿路。忽掩王身曰收，既得不捨曰執，故名收執也。言父者，別顯親之極也。王者，彰其位也。頻婆者，彰其名也。言幽閉七重室內者。所為既重，事亦非輕。不可淺禁人間，全無守護。但以王之宮閤，理絕外人，唯有群臣則久來承奉。若不嚴制，恐有情通。故使內外絕交，閉在七重之內也。

Third, from 'seized his father the king' down to 'not one was allowed to go [there],' it directly clarifies the father-king being imprisoned by his son. This clarifies that Ajātaśatru adopted Devadatta's evil scheme and abruptly abandoned the affection between father and son; not only did he fail in [repaying] boundless kindness, but the echo of his rebellion filled the roads because of this. Suddenly laying hold of the king's body is called 'seizing' (收); having taken him and not releasing him is called 'holding' (執); hence it is called 'seizing and holding.' The word 'father' distinctly displays the utmost intimacy of kinship. 'King' reveals his status. 'Bimbisāra' reveals his name. As for 'confined in a room behind sevenfold [walls],' because what was done was grave, the matter was also not light. It was impossible to detain him lightly among common people entirely without guards. But as the king's palace halls were, by principle, cut off from outsiders, only the assembly of ministers had served him for a long time. If [Ajātaśatru] did not strictly restrict them, he feared feelings might pass between them. Therefore, he caused internal and external contact to be severed, confining him within sevenfold walls.