1. Peace of Heart: The soul should be covered up with only the spirit of the prayer, praise of Allah, and the verses. One should break with worldly engagements. A soul that cannot break with the engagements of the world cannot concentrate on the prayer. It can never be aware of his/her presence before Allah. If the servant manages to overcome this forgetfulness, and manages union with Allah, and also benefits from the meanings of the recitations, then s/he acquires peace of mind/heart. Thus, men of Allah used to struggle to compensate for not only the prayers they did not perform properly, but also the ones they were not able to perform in peace of mind. However, this does not mean that everbody must act in the same way, but it demonstrates the importance of a sound heart in prayer.
The cause for peace of mind is spiritual endeavor. It is the desire to rise spiritually. And endeavor is actualized by comprehending that intimacy with Allah can only be attained through prayer.
2. Perception: One should perceive what he recites. This is the second important thing after peace of mind. And perception acts as a bridge in order that peace of mind in prayer be kept at other times as well.
3. Reverence: One should be aware of his being in the presence of Allah, and keep pious reverence both physically and spiritually. Namely, reverence means maintaining peace of mind, perception, and regulations in prayer. Maintaining these manners enhance the merit of the prayer and a prayer having these manners intercedes for the praying person on the Day of Judgment.
One should take into consideration the following warning:
"If you want your prayer to be an ascension, do not think that your worship is an excellent one in the face of the Grandeur of the Lord, and the blessings that Allah endowed you with! Do not ever think that your worship is enough to thank Allah! Think about the Prophet (pbuh) who used to say: 'O my Lord! I was not able to duly thank You; please forgive me!'"
4. Awe and Dread: The praying person should feel the awe and dread which come out of reverence. Awe and dread provide the praying person with an awareness of Allah's Power and Highness, and thereby earnestness and piety come out. Piety, namely, the awe of Allah, and protecting the heart from unawareness, are the most effective way of enhancing the rank of the servant before Allah. It is said in the Qur'an:
.".. The most honored of you in the sight of Allah is (he who is) the most righteous of you..." (Al-Hujurat 49: 13).
Abu Zarr narrates:
The Prophet (pbuh), one day, had gone out in the autumn. The leaves of trees were falling down. The Prophet (pbuh) then said:
"O Abu Zarr! There is no doubt that if a Muslim prays just for the sake of Allah with all his sincerity, his sins fall off him as these leaves fall off the trees." (Ahmad, Targib).
5. Hopeful Expectation: One is supposed to expect the Mercy of Allah during prayer, and appeal to Allah after the prayer as well. If one fears only, this condition makes the person sorrowful, and it may one day play havoc with our spiritual balance. Therefore, hopeful expectation eliminates this danger.
6. Modesty: This is a complementary virtue to the above mentioned merits. The servant who sees himself in the presence of Allah feels ashamed of his/her indecent behaviors, and therefore avoids them. Thus, he becomes aware of his lapses and oversight in prayer. He does not get obsessed with relying on his worship. The Prophet (pbuh) says in this regard:
"No one should ever rely on his sins being forgiven just because of his worship (prayer)." (Fadail-i Amal, 251).
Thus, one cannot guarantee that his sins would be forgiven because of prayer, and one should always remain ashamed of his indecent behavior as forgiveness is a Blessing and a Mercy from Allah. It is a requirement of His Compassion. Otherwise, we are unable to pray and thank the Lord adequately. However, prayers that are done in a humble and vigilant manner please Allah through His Beneficence and Blessing.
In short, one who does not combine the rhythm of the body with the awe of the heart cannot attain to the essence of prayer. One needs to strive to capture the essence of prayer both physically and spiritually. Those things that damage the union of body and spirit should be cleared away and the mind should be kept free of all kinds of distraction. The Prophet (pbuh), for example, says in this matter:
"When prayer and a meal overlap have the meal first!" (Bukhari, Muslim).