大乘百法明門論開宗義決 1.209

1.209

此二俱以安不安住身心分位所依等者。謂此尋伺若與定俱如理思惟即名為安。若時不能如理思惟不與定俱即名不安。尋求不安身心不安。尋伺若安身心安住。是故身心安不安住皆用尋伺為所依也。

"Both have as their basis the states of composure or non-composure of body and mind, etc.": this means that if these [factors of] investigation and analysis are accompanied by meditative absorption and attend [to things] according to reality, they are called 'composed.' If at [certain] times they cannot attend according to reality and are not accompanied by meditative absorption, they are called 'uncomposed.' When searching is uncomposed, body and mind are not at ease; when investigation and analysis are composed, body and mind abide in composure. Therefore, both the composure and non-composure of body and mind take investigation and analysis as their basis.