Thus, Imam Hussein (A.S) started making preparations for the journey. During midnight he went to the graves of his Mother Hazrat Fatimah (A.S) and his Brother Imam Hassan (A.S) to bid them farewell. In the morning when he returned to his home, his brother Muhammad ibne Hanafiyah came to him and said, "O dear brother! You are the most dear and beloved to me than anyone else. And I will not refuse to advise anyone except you, being most worthy of it, for you are from me, and are my life, my spirit and my eyes and the elder of my family. Your obedience is obligatory upon me for Allah has exalted you over me and has chosen you as the Master of the Youth of Paradise." Then he recited the entire Tradition narrated by the Prophet (PBUH) viz.
"Hassan and Hussein are the chiefs of the youth of Paradise."
Then he said, "I desire that you go to Mecca, if you find peace, stay there, and if the matter turns out to be different, then go to Yemen, for the people therein are among the helpers and followers of your Grandfather and Father. And they are the most kind-hearted and merciful among men, while their towns and cities are vast. Then if you can halt there then seek shelter in the deserts and mountain-caves and go from one town to the other until you witness the state of affairs of people, and may Allah judge between us and the group these of evil-doers."
Imam Hussein (A.S) replied: "O brother! Although there is no place left in this world for sheltering me, I shall never ever swear the oath of allegiance to Yazeed."
Then he said:
"O Brother! May Allah reward you favorably, for you have advised me and have opined righteously. As regards you O dear brother! You may stay behind in Medina and be alert and keep informing me about the affairs of the enemies."
Then Imam Hussein (A.S) asked for paper and pen and wrote the following recommendation for his brother Muhammad bin Hanafiyah:
"In the Name of Allah, the Beneficent, the Merciful. This contains that which has been willed by Hussein bin Ali bin Abi Talib to his brother Muhammad renowned as Ibne Hanafiyah. Verily Hussein bears witness that there is no Lord except Allah Alone. And bears witness that Muhammad (PBUH) is the Slave and the Messenger of Allah, who has been righteously chosen by Him. And that Paradise and hell are truth, and without doubt the Day of Judgment will come. And Allah will arise all those who are buried inside their graves. I have not risen to spread evil or to show off, nor for spreading immorality or oppression. But I have left for the betterment of the ummah of my Grandfather and I desire to propagate the Religion and forbid against evil, thus following the footsteps of my Grandfather and Father Ali bin Abi Talib (A.S). Thus the one who accepts truth through me, will have received truth from Allah, while the one who betrays me, I shall forebear until Allah judges between myself and the oppressive creed and verily Allah is the Best Judge. This is the testimony to you from me O brother. And my favor is with Allah Alone on Whom alone I rely, and my return is towards Him."
Then he folded the letter and affixed his seal on it and gave it to his brother Muhammad ibne Hanafiyah and bade him farewell and left in the darkness of the night.
source : tebyan