Abu Bakr Ibn Abu Dunya wrote in the book Ahkam-alQubur (The Rules of Graves), based on a long chain of citation, that the Prophet said: "Daniel prayed to his Lord, Great and Majestic for the nation of Muhammad to bury him." And he (i.e. Muhammad, PBUH) said: "Whoever discovers Daniel give him tidings of Paradise." The man who discovered him (his corpse) was called Harqus. Umar sent to Abu Musa saying: "Bury him; and send to Harqus, for the Prophet has given him promise of Paradise."
This hadith is mursal (it has a good chain of citation) as it is recorded, and Allah knows best.
Related Quran Ayaaths of this Hadith.
"When a person dies, his works end, except for three: ongoing charity, knowledge that is benefited from, and a righteous child who prays for him."
Prophet Mohammed (PBUH)
"The best of what a man leaves behind are three: a righteous child who supplicates for him, ongoing charity the reward of which reaches him, and knowledge that is acted upon after him."
Sunan Ibn Mājah
"Every day two angels come down from Heaven and one of them says, 'O Allah! Compensate every person who spends in Your Cause,' and the other (angel) says, 'O Allah! Destroy every miser.'"
Sahih Bukhari