A heart is inherently in need of God in two respects: One is worship, which is the "purposive reason," and the other is asking for God's aid and putting trust in Him, which is the "working reason." The heart, therefore, will never be useful, successful, blessed, pleased or satisfied except by worshipping God.
Supposing the heart obtained all the pleasures that creatures enjoy, it will never feel at rest or contented because there is in it "inherent need" to God. For in God alone the heart delights, and God alone is its adored beloved, and here the heart gets rest and satisfaction.
In fact, this will not happen but by the Providence and Help of God, for none but God can provide these things to the heart which is always in need of the fact that: "It is Thee we worship, and for Thy aid we ask" (Qur'an 1:5). If the heart was helped to obtain what it would like and want without worshipping God, it would obtain only pain, pity, and agony in this life, and it will never get rid of these unless God is its true love, and all other sorts of love are for His sake i.e. none will be loved for its own sake except God.
If this was not realized, the other fact cannot be realized, namely, "There is no God but Allah" (La ilaha illa Allah) neither can the other facts of Tawheed (Monotheism) - Slavery and Love of God, and he wlll have defective belief.
He who worked for this question while not asking for God's aid or putting trust in Him, or feeling poor and in need of Him, would not reach it. Whatever God willed, so it will be, and whatever He willed not, it won't. Man therefore is always in need of God Who is his aim and destination, and the worshipped Lord, whose help is sought, and in whom trust we put.
- Ibn Taymiyyah