It was narrated that Ibn 'Abbas said:
"When 'Umar became Muslim, Jibril came down and said: 'O Muhammed! The people of heaven are rejoicing because of 'Umar's Islam.'" (JA)
English reference (JA): Vol. 1, Book 1, Hadith 103 (JA)
Arabic reference (JA): Book 1, Hadith 108 (JA)