Thus, the first and fourth phrases say "God," the second, "Sustainer," and the third, "Truth." So understand how miraculously apt are the words: This is God, your Sustainer, The Truth.. It mentions Almighty God's vast disposals, the meaningful weavings of His power. Then through mentioning the Names of "God," "Sustainer," and "Truth," it shows the source of those vast disposals of Divine power.
An example of the second:
Behold! In the creation of the heavens and the earth; in the alternation of the night and the day; in the sailing of the ships through the oceans for the profit of mankind; in the rain which God sends down from the skies, and the life He gives therewith to an earth that is dead; in the beasts of all kinds that He scatters through the earth; in the disposal of the winds and the clouds subjugated between the sky and the earth, indeed are signs for people who think.122
First this enumerates the manifestations of Divine sovereignty in the creation of the heavens and the earth, which demonstrates Almighty God's perfect power and the vastness of His dominicality, and testifies to His unity; and the manifestation of dominicality in the alternation of night and day, and the manifestation of Divine mercy in the subjugation of the ships in the sea, the most important means of transport in human social life; and the manifestation of the immensity of Divine power, which sends the water of life to the dead earth from the skies and raises to life hundreds of thousands of species and makes it like a exhibition of wonders; and the manifestation of mercy and power in the creation of infinite numbers of different animals on the earth from simple soil; and the manifestation of wisdom and mercy in the employment of the winds in important duties like assisting in the pollination and respiration of plants and animals and in the impelling and regulating of them so as to make them suitable to perform those duties; and the manifestation of dominicality in the subjugation and gathering together of the clouds, the means of mercy, suspended between the skies and the earth in great strange masses, and dispersing them, as though dispersing an army for rest and then summoning them back to their duties. Then, in order to urge the mind to ponder over their details and essential truths, it says: Indeed are signs for people who think. In order to rouse people's minds with it, it refers it to their faculties of reason.
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122.Qur'an 2:164