God revealed to Da’ud (peace be upon him): You think that you love Me. If you love Me, give up your love for the world from your mind, because love for Me and love for the world cannot unite in the mind of man. O Da’ud, love Me sincerely and mix with the people of the world outwardly and observe religion for Me and not for man.
Remember what is in conformity with My love and rely on Me what seems difficult to you. I have kept you before upon guidance and control, I become now your Guide and Proof. I give you before you ask. I help you in your dangers and difficulties. I swear by Myself that I will not give rewards except to one whom I know to be reliant on Me and whose search and will are sincere and selfless.
O Da’ud, when you cannot remain satisfied without Me, I become likewise for you. I remove disgrace and solicitude from you and give satisfaction to your mind, as I have inflicted promise on Myself that whoever remains satisfied with his work, I entrust him to himself. Ascribe everything to Me, so that your deeds may not go against you and you may not be a helping hand to sins and your companions may not be deprived of your good. You will find no limit and end to the knowledge of My Ma’rifat.
O Da’ud, don’t make such a learned man an intermediary between you and Me who casts screen over My love. They are robbers for those who are desirous of My love. Give up greed always by the help of fasting.
Be careful of giving up fast as I know that love for Me by the help of fasting is dear to Me. O Da’ud, love Me by going against your baser self. I will then prevent your greed and I will look at you. You will ten see that the screen between you and Me has been lifted. The reason is that I shall have to give you rewards and I will help you for the reason that you may be fit for this reward. Hold fast to allegiance to Me.
O Da’ud, had those persons desirous of My love known how I remain anxious for them, how I shower My favors on them, how I wish that they should give up sins, they would have surely died being attached to Me and their glands would have been cut off on account of their love for Me.
O Da’ud, this is My wish in connection with those who work hard for Me. How anxious am I for those who advance towards Me. O Da’ud, when a man becomes independent of Me, he becomes more needy of Me than his other conditions. When a man turns away from Me, I feel sympathy for him. When he returns to Me, he seems to Me to be good.
Hujjatul Islam, Imam Abu Hamid al-Ghazali; Ihya’ Ulum-id-Din (Revival of Religious Learnings), Book of Constructive Virtues