What is meant by "righteous deeds" as mentioned in the Holy Quran?

Righteous deeds are those that combine two elements: sincerity of intention for Allah, and the conformity of the action to the Sunnah of the Prophet, peace and blessings be upon him. This is because the fundamental principle of the religion is that none is worshipped except Allah alone, and He is worshipped only by what He has legislated through His Messenger, which is the essence of the two declarations of faith (Shahadatayn). Al-Fudayl ibn Iyad said concerning the verse: (That He might test you, which of you is best in deed) [Hud:7]: "The most sincere and the most correct." For a deed is not accepted unless it is both sincere and correct. The sincere deed is that which is for Allah, and the correct deed is that which conforms to the Sunnah.