淨名經集解關中疏 2.168

2.168

曰。無所得故而得　二答也。謂斷九地惑故無得。得第九解脫故而得。

[Śāriputra] said: "Because there is nothing to attain, I attained it." Second, the answer. This means that by severing the defilements of the nine grounds, there is nothing attained; by attaining the ninth liberation, one attains it.