分別功德論 2.23

2.23

念施所以得至涅槃者，以施有財施、法施也。因財施得達法施，成檀度無極故，得至涅槃也。

As for why mindfulness of giving (tyāgānusmṛti) enables one to reach nirvāṇa: it is because giving includes both the giving of material wealth and the giving of Dharma. Relying on the giving of wealth, one is able to attain the giving of Dharma; completing the boundless perfection of giving (dānapāramitā), one is therefore able to reach nirvāṇa.