Al-Anfal · 8:63

63. He brought the hearts of the believers, with whom He assisted you, together after they were disunited. If you had spent all the wealth on earth to bring their disunited hearts together, you would not have been able to do so. But Allah alone brought them together. He is Mighty in His dominion and nothing can overpower Him. He is Wise in His decree, handling of affairs and sacred laws.