Translation of the letter:
One of our companions informed us, he said: I wrote to Mansoor Hashimi Khorasani, may God support him, and asked him to write to me every action that I must do after knowing the truth and supporting it to be among the successful. So he wrote to me:
“And thereafter…
[1] Perform prayer at the beginning of its time.
[2] Do not abandon the nafilah of night and seek forgiveness at dawn.
[3] If you are able to not neglect the remembrance of God for a moment, then do so; because neglecting His remembrance is the root cause of every sin.
[4] Remember death often and go visit the graves; because you will not stay on the earth but a short time.
[5] Fast on the first and last Thursday and the middle Wednesday of every (lunar) month; because it is Sunnah.
[6] Give alms; because it atones for your evil deeds.
[7] Do good to your parents, even if they mistreat you; because they have done good to you well enough.
[8] Do not sever your kinship ties, even if it hangs by something like a hair.
[9] Do not lie unless you fear that you will be killed or get somebody killed.
[10] Do not backbite except about one who is a disbeliever or a sinner. So when you complain about those who are absent, say: “What is the matter with people who do such-and-such or say such-and-such,” and do not mention them by name.
[11] Avoid arguing, even if you are right, but rather bring your proof and remain silent, even if you are accused of being defeated.
[12] Admit your mistake, even if you are humiliated.
[13] Forbid every wrong that you see and enjoin every right that you do not see; because it is the key to reforming the world.
[14] Do not talk too much to stay safe; because talking too much is not without flaws.
[15] Do not joke unless you speak the truth.
[16] Do not insult or slander anyone, even if in your opinion he deserves to be killed.
[17] Fulfill your promise, even if it is to a child.
[18] Do not disgrace a believer or you will be disgraced.
[19] Do not get angry unless you restrain it; because anger is one of the gates of Hell.
[20] Do not be strict with people so that they will not be strict with you; i.e., do not find fault, scrutinize, gloat, or retaliate.
[21] Do not entrust your works to others except when you are unable (to do them).
[22] Do not fill your stomach, nor eat what does not suit your temperament.
[23] Your sexual desire is a hungry, sleeping monster. Beware, do not wake it or it will eat you.
[24] Do not express an opinion on something of which you have no knowledge or you will come up with absurd words.
[25] Do not sleep less than five hours or more than eight hours or you will harm yourself.
[26] Do not mention any news you hear, for it may be a lie.
[27] Your time is more valuable than diamond; so do not spend it playing or doing useless things.
[28] You need to study, for there is still much you do not know.
[29] You need to do exercise, for a strong believer is better than a weak believer.
[30] Be clean and well-groomed, even if you have on a newspaper.
I ask God for success and forgiveness for myself and you, and peace be upon you and whoever follows the guidance.”
Explanation of the letter:
The believing men and women must know the value of this invaluable letter and use it as a plan to purify themselves so that in this way, they will draw near to God Almighty and be ready to help His Caliph on the earth, Imam Mahdi 
.
