448.Muhammad (peace be upon him) said: "O Abu Zarr (a Sahaabi) if you go anywhere to learn one ayaat of the Qur'aan, it is better for you than a hundred rakaats (Nafal) Salaat; if you go anywhere to acquire one law of the knowledge (of Deen), it is better for you than performing a thousand rakaats (Nafal) Salaat, irrespective of whether you practised on it (the knowledge) or not."
(Ibn Majah).
(Hayaat-ul-Muslimeen. by Maulana Mohammad Ali Thanvi).