首楞嚴義疏注經 4.307

4.307

由無三緣，方盡三因，因緣俱滅，菩提始顯，故云皎然明白。小乘開悟皆由因緣，故引昔悟以竝今說，成此難也。

Only because there are no three conditions are the three causes completely exhausted; when causes and conditions are both extinguished, bodhi first manifests; hence he says "clearly and plainly evident." The awakenings of the Hīnayāna all proceed from causes and conditions; therefore, he cites his past awakening alongside the present explanation to form this objection.