Narrated ‘Umar (rad):

Allah’s Messenger (ﷺ) said: “If one after performing ablution completely recites the following supplication: (Ash-hadu an la ilaha ill-Allahu wahdahu la sharika lahu, wa ash hadu anna Muhammadan ‘abduhu wa Rasuluhu) ‘I testify that there is no one worthy of worship but Allah, He is Alone and has no partner and Muhammad (ﷺ) is his slave and Messenger’, all the eight gates of Paradise will be opened for him and he may enter through any gate he wishes”.

وَعَنْ عُمَرَ ‏- رضى الله عنه ‏- قَالَ: قَالَ رَسُولُ اَللَّهِ ‏- صلى الله عليه وسلم ‏-{ مَا مِنْكُمْ مِنْ أَحَدٍ يَتَوَضَّأُ, فَيُسْبِغُ اَلْوُضُوءَ, ثُمَّ يَقُولُ: أَشْهَدُ أَنْ لَا إِلَهَ إِلَّا اَللَّهُ وَحْدَهُ لَا شَرِيكَ لَهُ, وَأَشْهَدُ أَنَّ مُحَمَّدًا عَبْدُهُ وَرَسُولُهُ, إِلَّا فُتِحَتْ لَهُ أَبْوَابُ اَلْجَنَّةِ" } أَخْرَجَهُ مُسْلِم ٌ [1]‏ .‏