Skandapurana 5.246.35

5.246.35

śruto harati pāpaṃ ca janmādi maraṇāvadhi ..
aśvatthasevanaṃ puṇyaṃ cāturmāsye viśeṣataḥ .. 34 ..
supte deve vṛkṣamadhyamāsthāya bhagavānprabhuḥ ..
jalaṃ pṛthvīgataṃ sarvaṃ prapibanniva sevate .. 35 ..

And when heard [of], it removes sin up to the end of life from birth onward. / The veneration of the aśvattha is meritorious, especially during Cāturmāsya.
While the Lord is asleep, having entered the interior of the tree, the blessed sovereign Lord / dwells there, as if drinking up all the water residing upon the earth.