﴿ قَالَ أَبَشَّرْتُمُونِى عَلَىٰٓ أَن مَّسَّنِىَ ٱلْكِبَرُ فَبِمَ تُبَشِّرُونَ ﴾

“Said he: "Do you give me this glad tiding despite the fact that old age has overtaken me? Of what [strange thing], then, are you giving me a tiding!"”

Please check ayah 15:56 for complete tafsir.