大乘起信論義記 3.468

3.468

謂修大乘菩薩行者，要依此真如三昧，方入種性不退位中，除此更無能入之路，故云若諸凡夫乃至無有是處也。此中種性者，約位在十住已去不退位中辨也。

This means that a practitioner cultivating the bodhisattva practice of the Mahāyāna must rely on this samādhi of tathatā in order to enter the lineage, the stage of non-retrogression; other than this, there is no road by which one can enter. Hence it says, 'If ordinary persons [...] it is impossible.' Here, 'lineage' is explained in terms of the stage of non-retrogression from the ten abodes onward.