"The Messenger of Allah (ﷺ) asked me: 'How will you act, Abu Dharr, when you are under rulers who kill prayer or delay it (beyond its proper time) ?' I said: 'Messenger of Allah, what do you command me ?' He replied: 'Offer the prayer at its proper time, and if you say it along with them, say it, for it will be a supererogatory prayer for you.'"
Sunan Abi Dawud Book 2, Hadith 41
← Previous Hadith Allah , the Exalted said: I made five times' prayers obligatory on your people, and I took a guarantee that if anyone observes them regularly at their times, I shall admit him to Paradise; if anyone does not offer them regularly, there is no such guarantee of Mine for him.

Sunan Abi Dawud Book 2, Hadith 40 Next Hadith → Amr ibn Maymun al-Awdi said: Mu'adh ibn Jabal, the Messenger of the Messenger of Allah (ﷺ) came to us in Yemen, I heard his takbir (utterance of AllahuAkbar) in the dawn prayer. He was a man with loud voice. I began to love him. I did depart from him until I buried him dead in Syria (i.e. until his death).

Then I searched for a person who had deep understanding in religion amongst the people after him. So I came to Ibn Mas'ud and remained in his company until his death. He (Ibn Mas'ud) said: The Messenger of Allah (ﷺ) said to me: How will you act when you are ruled by rulers who say prayer beyond its proper time? I said: What do you command me, Messenger of Allah, if I witness such a time? He replied: Offer the prayer at its proper time and also say your prayer along with them as a supererogatory prayer.

Sunan Abi Dawud Book 2, Hadith 42