To make the Heart Tender (Ar-Riqaq)
Bukhari :: Book 8 :: Volume 76 :: Hadith 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."