Laa ilaaha ill-Allaah wahdahu laa shareeka lah, lahu’l-mulk wa lahu’l-hamd yuhyi wa yumeet wa huwa ‘ala kulli shay’in qadeer

لاَ إِلَهَ إِلاَّ اللَّهُ وَحْدَهُ لاَ شَرِيكَ لَهُ لَهُ الْمُلْكُ وَلَهُ الْحَمْدُ يحي و يميت وَهُوَ عَلَى كُلِّ شَيْءٍ قَدِيرٌ.

Laa ilaaha ill-Allaah wahdahu laa shareeka lah, lahu’l-mulk wa lahu’l-hamd yuhyi wa yumeet wa huwa ‘ala kulli shay’in qadeer* 

* = 1 time after every fardh prayer, except Maghrib and Fajr wherein this has to be recited 10 times) 

There is no God but Allaah alone, with no partner or associate, His is the Dominion and to Him be praise, He gives life and gives death, and He has power over all things

[Reference: Muslim 1/418, Ahmad, At-Tirmithi 5/515, Ahmad 4/227. See its checking in Ibn Al-Qayyim Al-Jawziyyah’s Zddul-Ma’ad 1/300] 

Virtue: 

مَنْ قَالَ لاَ إِلَهَ إِلاَّ اللَّهُ وَحْدَهُ لاَ شَرِيكَ لَهُ لَهُ الْمُلْكُ وَلَهُ الْحَمْدُ يُحْيِي وَيُمِيتُ وَهُوَ عَلَى كُلِّ شَيْءٍ قَدِيرٌ . عَشْرَ مَرَّاتٍ عَلَى إِثْرِ الْمَغْرِبِ بَعَثَ اللَّهُ لَهُ مَسْلَحَةً يَحْفَظُونَهُ مِنَ الشَّيْطَانِ حَتَّى يُصْبِحَ وَكَتَبَ اللَّهُ لَهُ بِهَا عَشْرَ حَسَنَاتٍ مُوجِبَاتٍ وَمَحَا عَنْهُ عَشْرَ سَيِّئَاتٍ مُوبِقَاتٍ وَكَانَتْ لَهُ بِعَدْلِ عَشْرِ رِقَابٍ مُؤْمِنَاتٍ 
Umarah bin Shabib As-Saba’i narrated that the Messenger of Allah said:“Whoever says: none has the right to be worshipped but Allah, Alone, without partner, to Him belongs all that exists, and to Him belongs the praise, He gives life and causes death, and He is powerful over all things, (La Ilaha Illallahu Wahdahu La Sharika Lahu Lahul-Mulku Wa Lahul-Hamdu, Yuhyi Wa Yumitu Wa Huwa ala Kulli Shai’in Qadir)’ ten times at the end of Al-Maghrib – Allah shall send for him protectors to guard him from Shaitan until he reaches morning, and Allah writes for him ten good deeds, Mujibat, and He wipes from him ten of the destructive evil deeds, and it shall be for him the equal of freeing ten believing slaves.” 
[Jami` at-Tirmidhi 3534; 3468; Sunan Ibn Majah 3798; Muwatta Maalik Book 15, Hadith 20; Sahih Muslim Book 35, Hadith 6508, graded as Hassan by Albaani, Ibn Hajar, al-Mundhari and others