Imam Hussein's sacrifice prevented the deviation of Islam and the Prophet's path
The Islamic Ummah should never forget the event of Ashura which is a lesson and a source of guidance for us. Definitely, Islam is alive because of the event of Ashura and the efforts of Hussein ibn Ali (a.s.).
"And I am from Hussein." This narration means that Hussein (a.s.) continued the path of the Holy Prophet (s.w.a.) and he continued to promote Islam after him. If it had not been for the event of Ashura and if these great sacrifices had not been made in the history of Islam, this valuable experience and this practical lesson would not have been bestowed on the Islamic Ummah and Islam would have definitely deviated from its path - as many religions before Islam did - and nothing would have remained from it. The greatness of Ashura is because of this.