وَيَسْتَنبِئُونَكَ أَحَقّ هُوَ قُلْ إِي وَرَبّي إِنّهُ لَحَقّ وَمَا أَنتُم بِمُعْجِزِينَ They seek to be informed by thee: “Is that true?” Say: “Aye! by my Lord! it is the very truth! and ye cannot frustrate it!” – Quran: 10:53

أرسل عمر إلى عائشة : ائذني لي أن أدفن مع صاحبي ، فقالت : إي والله Umar sent a message to Aishah, ‘Permit me that I may be buried with my two companions’, and she said, ‘Yes, by God!’ – Bukhari

Did you know…

إي is one of a number of words in Classical Arabic used to mean “yes!”. It has to be followed by an oath, such as in the two examples above. From إي والله Yes, By God!, we get the modern colloquial word for yes: aiwah!