俱舍論記 20.20

20.20

「若自謂是至一切有宗」者，釋下兩句。若自謂是說一切有宗，決定應許實有去、來世，以說三世皆定實有，故許是說一切有宗。

Regarding "If one considers oneself to be ... the Sarvāstivāda school": this explains the next two lines. If one considers oneself to belong to the Sarvāstivāda school, one must definitively admit that past and future periods are substantially existent; because one states that all three periods are definitively and substantially existent, one is admitted to belong to the Sarvāstivāda school.