It wasnarrated that 'Umar bin Al-Khattab said:
"The Prophet (ﷺ)saidto me: 'When you enter upon one who is sick, tell him to pray foryou, for his supplication is like the supplication of the angels.'" (RU)
English reference (RU): Vol. 1, Book 6, Hadith 1441 (RU)
Arabic reference (RU): Book 6, Hadith 1508 (RU)