釋氏要覽 1.163

1.163

中阿含經云。佛入禪室燕坐。又有呼為禪齋。齋者肅靜義也。如儒中靜室謂之書齋。或官員判吏靜治之處。謂之郡齋。

The Madhyamāgama says that the Buddha entered the meditation chamber to sit in quiet seclusion. It is also called a meditation retreat (zhaizhai); 'zhai' has the sense of reverent stillness. Just as among Confucians a quiet room is called a study (shuzhai), or the place where government officials and magistrates deliberate in quiet governance is called a prefectural retreat (junzhai).