Sahih Bukhari
To make the Heart Tender (Ar-Riqaq)
Volume: 008 / Book Number: 076 / Hadith Number: 424
Narrated Sahl:
I heard the Prophet saying, "A (small) place equal to an area occupied by a whip in Paradise is better than the (whole) world and whatever is in it; and an undertaking (journey) in the forenoon or in the afternoon for Allah's Cause, is better than the whole world and whatever is in it."