Sahih Adab al-Mufrad

It is narrated from Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him): When you are under a ruler whose harshness and oppression you fear, then say «اللهم رب السماوات السبع ورب العرش العظيم ، كن لي جاراً من فلان بن فلان وأحزابه من خلائقك؛ أن يفرط على أحد منهم ، أو يطغى ، عز جارك ، وجل ثناؤك ، ولا إله إلا أنت» "O Allah! Lord of the seven heavens and Lord of the Mighty Throne, be my protector against so-and-so son of so-and-so from among Your creation and his group, lest any of them attack me or do injustice to me. Your protection is mighty, and Your praise is great, and there is no deity except You."