﴿ قَالَ رَبِّ أَنَّىٰ يَكُونُ لِى غُلَٰمٌۭ وَكَانَتِ ٱمْرَأَتِى عَاقِرًۭا وَقَدْ بَلَغْتُ مِنَ ٱلْكِبَرِ عِتِيًّۭا ﴾

“[Zachariah] exclaimed: "O my Sustainer! How can I have a son when my wife has always been barren and I have become utterly infirm through old age?"”

This prayer was answered by the granting of a son—an extraordinary happening, as a son is not ordinarily born to people in such circumstances. The birth of a child to a couple, where the husband was extremely old and his wife had been barren throughout her life, was really a most unusual event. On account of this, Zachariah’s pleasure on receipt of this extraordinary and unexpected news spontaneously expressed itself as disbelief: how could he have a child when he and his wife were incapable of having children?