It is narrated from Sayyidah Maymunah (may Allah be pleased with her) that the Prophet (peace and blessings be upon him) took the ritual bath at her house; she brought him (peace and blessings be upon him) a towel, but he (peace and blessings be upon him) did not take it. Al-A'mash said: I mentioned it to Ibrahim, and he said: The matter is like that, and there is no harm in drying with a towel; it is only a matter of habit.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الطهارة / 875