Meaning of Best Deeds:
“He is the One who created death and life to test you as to which of you is best in deed.” (Surah Al-Mulk, Ayat 2)
Imam Ja’far al-Sadiq (peace be upon him) explained:
“It does not mean who does the most deeds, but who does the most correct deeds. Correct deeds are those that include God-consciousness and pure intentions.”
He further stated, “Protecting a deed from impurity is more difficult than performing the deed itself.”
Pure and Righteous Actions:
A sincere and righteous action is one where you do not desire anyone other than Allah to praise you for that deed.
Reference:
Book: Tafsir Nemooneh, Volume 14, Page 104
By: Ayatollah Nasir Makarem Shirazi