Muhammad ibn Abi Bakr
At the time, Muhammad ibn Abi Bakr was the governor of Egypt. Amr ibn al-As, one of Mu'awiyah's companions, wanted to become the governor of Egypt. So he rallied 6,000 soldiers and headed towards Egypt. After finding out about the possible overthrow, Muhammad ibn Abi Bakr wrote to Ali Ibn Abi Talib asking for help and support. Ali Ibn Abi Talib wrote back assuring Muhammad ibn Abi Bakr, son of the first caliph and then Ali's adopted son, that he is sending his best general and one of his closest companions, Malik al-Ashtar. Ali then told Malik: "Malik, may Allah have mercy on you, go to Egypt. I have absolute trust in you. Rely on Allah! Use gentleness in its place and intensity in its place."