Hadith 17:677
Abu Bakr narrated to us, he said: Waki’ narrated to us, from Shu’bah, from al-Nu’man ibn Salim, from ‘Abdullah ibn ‘Umar, that a man sneezed in his presence, so he said "Yarhamuk Allah" (may Allah have mercy on you) to him. Then he sneezed again, so he said "Yarhamuk Allah" to him. Then he did it a third time, so he said: "You are suffering from a cold."
حدثنا أبو بكر قال حدثنا وكيع عن شعبة عن النعمان بن سالم عن عبد الله بن عمر أن رجلا عطس عنده فشمته ثم عطس فشمته ثم عاد في الثالثة فقال إنك مضنوك