The Messenger of Allaah (Sallallaahu 'alayhi wasallam) said:
(( خَيرُ الدُّعَاءِ : دُعَاءُ يَومِ عَرَفَةَ ، وَ خَيرُ مَا قُلْتُ أَنَا وَ النَّبِيُّونَ مِنْ قَبْلِي : لاَ إِلَهَ إِلاَّ اللهُ ، وَحْدَهُ لاَ شَرِيكَ لَهُ ، لَهُ المُلكُ ،
وَ لَهُ الحَمدُ ، وَ هُوَ عَلَى كُلِّ شَيءٍ قَدِيرٌ ))
"The best du'aa is the du'aa on the Day of 'Arafah, and the best thing that I and the Prophets before me said is:
'Laa ilaaha illallaah, wahdahu laa shareeka lah, lahul-Mulku
wa lahul-hamd, wa huwa 'alaa kulli shayin qadeer'."
(There is nothing that deserves to be worshipped in truth except Allaah, He is Alone and has no partner, to Him belongs the dominion and to Him belongs all praise, and He is All-Powerful over all things) [1]
