And it is He who created the heavens and earth in truth. (6:73)

Almuntakhab Fi Tafsir Alquran Alkarim

He is it Who created the heavens and the earth in truth and with a set of invariable cosmic laws in all manner of wisdom and for a valid reason. The instant He says to an object or to an event Be it is there. His Word is the truth personified and to Him belong the absolute sovereignty and the full control of the Eventful Event when the trumpet is sounded indicative of Resurrection and Judgement. He is the Omniscient of the invisible, the hidden and the unseen, the Omniscient of what the breasts store of thoughts and feelings and of what they forge. He has cognizance and holds prescience of what you converse secretly and utter below your breath and of what is suggested secretly to the mind. He is well acquainted with the visible and the seen and with what is avowed openly and openly disclosed, with all that is uttered loudly and with all that is being said. He is Al Hakim (he Source of wisdom and wise mysterious dispensations) and AL-Khabir (The Omniscient)

Tafseer Tafheem-ul-Quran by Syed Abu-al-A'la Maududi

(6:73) And He it is Who has created the heavens and the earth in truth; *46 and the very day He will say: "Be!" (resurrection) there will be. His word is the Truth and His will be the dominion *47 on the day when the-Trumpet is blown. *48 He knows all that lies beyond the reach of human perception as well as all that is visible to man; *49 He is the All-Wise, the All-Aware.'

And it is He who created the heavens and earth in truth. meaning

*46). It has been asserted again and again in the Qur'an that God created the heavens and the earth 'in truth'. This covers a wide range of meanings:
First, that the heavens and the earth have not been created just for the fun of it. This existence is not a theatrical play. This world is not a child's toy with which to amuse oneself as long as one wishes before crushing it to bits and throwing it away. Creation is rather an act of great seriousness. A great objective motivates it, and a wise purpose underlies it. Hence, after the lapse of a certain stage it is necessary for the Creator to take full account of the work that has been done and to use those results as the basis for the next stage. This is stated at various places in the Qur'an in the following manner:
Our Lord, You did not create this in vain (Surah Al 'Imran 3:191).
And We did not create the heavens and the earth and whatever lies in between them playfully (Surah Al-Anbiya' 21:16).
And did you think that We created you out of play and that you will not be brought back to Us? (Surah al-Mu'minun 23:115).
Second, it means that God has created this entire system of the universe on solid foundations of truth. The whole of the universe is based on justice, wisdom and truth. Hence, there is no scope in thesystem for falsehood to take root and prosper. The phenomenon of the prosperity of falsehood which we observe, is to be ascribed to the will of God, Who grants the followers of falsehood the opportunity, if they so wish, to expend their efforts in promoting unrighteousness, injustice and untruth. In the end, however, the earth wfll throw up all the seeds of untruth that have been sown, and in the final reckoning every follower of falsehood will see that the efforts he devoted to cultivating and watering this pernicious tree have all gone to waste.
Third, it means that God has founded the universe on the basis of right, and it is on the ground of being its Creator that He governs it. His command in the universe is supreme since He alone has the right to govern it, the universe being nothing but His creation. If anyone else's commands seem to be carried out in this world, this should not cause any misunderstanding. For in reality the will of no one prevails, and cannot prevail in the universe, for no one has any right to enforce his will.
*47). This does not mean that the present dominion is not His. The purpose of this statement is rather to stress that when the veil which keeps things covered during the present phase of existence is lifted and the Truth becomes fully manifest, it will become quite clear that all those who seemed or were considered to possess power and authority are absolutely powerless, and that the true dominion belongs to the One True God Who created the universe.
*48). In what manner the Trumpet will be blown is difficult for us to grasp.What we know through the Qur'an is that on the Day of Judgement the Trumpet will be blown on God's command, whereupon all will die. Then after an indefinite period of time - a period that is known to God alone - the second Trumpet will be blown, whereupon all people of all epochs will be resurrected and will find themselves on the Plane of the Congregation.
Thus, when the first Trumpet is blown the entire order of the universe will be disrupted, while on the blowing of the second Trumpet a fresh order will be established, in a new form and with a new set of laws governing it.
*49). Ghayb signifies all that is hidden from, and is beyond the ken of man's knowledge. Shahadah, as opposed to ghayb, signifies that which is manifest and thus can be known to man.
 

And it is He who created the heavens and earth in truth. meaning in Urdu

وہی ہے جس نے آسمان و زمین کو بر حق پیدا کیا ہے اور جس د ن وہ کہے گا کہ حشر ہو جائے اسی دن وہ ہو جائے گا اس کا ارشاد عین حق ہے اور جس روز صور پھونکا جائیگا اس روز پادشاہی اُسی کی ہوگی، وہ غیب اور شہادت ہر چیز کا عالم ہے اور دانا اور باخبر ہے