It is narrated from Sayyiduna Ibn Umar (may Allah be pleased with them both) that when the Prophet (peace and blessings be upon him) returned from Hajj, Jihad, or Umrah, he would first say Allahu Akbar three times, then recite this supplication: "Allah is the Greatest, Allah is the Greatest, there is no deity except Allah, He is alone, He has no partner, His is the dominion and His is the praise, and He has power over all things. We are returning repentant, prostrating, worshipping, and praising our Lord. Allah has fulfilled His promise, helped His servant, and defeated all the armies alone."