Musnad Ahmad 30:1740

Sulayman narrated to us, Isma'il informed us, Muhammad—meaning Ibn 'Amr—informed me, from Abu Salamah, from Abu Hurayrah, that the Prophet (peace and blessings of Allah be upon him) said: "Allah called Jibril and sent him to Paradise, and said: 'Look at it and at what I have prepared for its people.' So he returned to Him and said: 'By Your Might, no one hears of it except that he enters it.' Then it was veiled with hardships. He said: 'Return to it and look at it.' So he returned to it, and said: 'By Your Might, I fear that no one will enter it.' Then He sent him to the Fire, and said: 'Go and look at it and at what I have prepared for its people in it.' So he returned to Him and said: 'By Your Might, no one who hears of it will enter it.' Then it was veiled with desires. Then He said: 'Return to it and look at it.' So he returned to it, and said: 'By Your Might, I fear that there will remain no one except that he enters it.'"