When a person is involved in his daily affairs and he neglects death and the eternal life, he gets ready for engaging in all sorts of sins and wrong-doing and surrenders to the temptations of Satan and to the whims and desires of his self. The most significant factor which could tame his aggressive self is the remembrance of Death and the instability of this world and the events of the next world.

In fact, if we pay attention, we will see that sooner or later death will overcome a person and he will be put in the grave and his limbs will disintegrate and turn into earth. He will cut his relations with his wealth, children, house and the world as such. He will, pretty soon, be forgotten as if he had not been living. But he is responsible now for what he had done before. Now he wishes he had never been born to take this burden of sins on his shoulders.
For this very reason it is emphasized in the Islamic traditions to remember death. The Prophet of Islam has said:

"The best asceticism in this world is the remembrance of death; the best worship is the remembrance of death, and the best contemplation is the remembrance of death. One on whom the remembrance of death weighs heavily, will find his grave to be one of the gardens of Paradise."

Imam ‘Ali (as) has said:

"Remember the destroyer of pleasures, the terminator of desires, the inviter to separations. Remember the disperser of groups, the remover of hopes, the one that draws near what is to be forgotten, the announcer of partings and dispersions."

Imam Sadiq (as) has said:

"The remembrance of death kills desires in the soul, cuts off the sources of heedlessness and strengthens the heart through Allah's promises; it softens the temperament, breaks the sign-posts of whims, puts out the fire of greed and makes the world appear miserable and worthless."

It is also narrated from Imam ‘Ali (as) his saying:

"Remember death frequently, and the day you will be resurrected from the graves and your standing before Allah; this remembrance will ease your disasters."

The Prophet (S) has said:

"If animals knew what we know of death, you would never eat a fat animal."

Once a man’s name was mentioned in the presence of the Prophet (S) and he was praised. The Prophet (S) asked: “Did he remember death”? The attendants answered: “We don't remember him saying anything about death”. The Prophet (S) said: “Then he is not to be praised”.
The Prophet was asked:

“O Messenger of Allah, who are the cleverest people”? He answered: “Those who are the most frequent in the remembrance of death and the firmest in readiness for it - those are clever ones who have taken the honor of this world and the favours of the Hereafter."

It is also narrated from the Prophet (S) that he said, "One who does not take a lesson from death and does not remember his misery and long stay in the grave and his bewilderment on the Day of Judgment, is not prosperous. Anybody in this world who does not care for death will be inflicted with sorrows in this world and anybody whose remembrance of death is good in this world is prosperous"

There are two groups of people regarding death:
The first group severely escapes the remembrance of death and these are people who do not believe in the Hereafter and whose behavior in the world has been indecent. They know that by death they will get deprived of what they have.

Imam al-Husayn (as) was once asked: “Why are we frightened of death and are not interested in it”? Imam answered: “Because you have destroyed your Hereafter but have constructed your world. That is why you are frightened to move from flourishing condition to ruined condition".
The second group includes those who do not fear death. These are people who believe in the Hereafter and its assets, who have acted in accordance with the commands of Allah, who believe that by breaking the cage of the body here, they will enjoy Allah's blessings in the Hereafter. Thus, they not only do not fear death, but also consider it sweeter than honey. They repeat the following:
Tell death to come to me if it is a man,
Till I embrace him very closely;
I'll receive an eternal life from him,
He'll receive from me colored clothing
Kill me; kill me, O Great one,
For in your killing there is life.

Imam ‘Ali (as) has said:

"The best gift for a believer is death"

Imam Sadiq (as) has said:

“In death lies the salvation of the sincere ones and the destruction of the evildoers. For this reason, some love death and others dislike it. The Great Prophet (S) has said: One who loves meeting Allah, Allah loves meeting him; and one who dislikes meeting Allah, Allah dislikes meeting him."

With a concern to what we have so far said, we will appreciate the educational value of Imam ‘Ali's statement that: Make you heart submissive with the remembrance of death.