Do what you are able to do

On the authority of Abu Hurayra Abd ar-Rahman ibn Sakhr (may Allah be pleased with him), who heard the Messenger of Allah (may Allah bless him and grant him peace) say: "Avoid what I have forbidden you, and do of what I have commanded you as much as you are able. What destroyed the nations before you was their many questions and their disagreement with their prophets."

Related by al-Bukhari and Muslim.

[al-Bukhari 7288; Muslim 1337]