阿彌陀經疏 1.237

1.237

經曰：「若有人已發願、今發願、當發願，欲生阿彌陀佛國」，次釋第一發心也。已發願者是過去，今發願者是現在，當發願者是未來，欲生等者一心希望也。

The sūtra says: 'If there are people who have already made the vow, are now making the vow, or will make the vow, wishing to be born in Amitābha Buddha's land...' Next, this is the first part of the commentary, on generating the mind. 'Have already made the vow' refers to the past; 'are now making the vow' refers to the present; 'will make the vow' refers to the future. 'Wishing to be born...' refers to single-minded aspiration.