That is because Allah— He is the Truth , and what you call upon besides Him is falsehood. Allah is the All-High, the Most Great. (Surah Luqman, 31:30)
As is the case with all living and non-living beings, space and time are also created concepts. In a moment when space and time were non-existent, the universe was suddenly created from non-existence, and from within this universe emerged the concepts of space and time. Indeed, as we go back in time, we encounter a limit that we can never cross: the moment the universe was created. Modern science has determined this limit to be 10-43 seconds after the moment the universe was created. Before this, space and time could not be defined.
At this point, we encounter a dimension in which space and time did not exist. As these two concepts that limit humanity were “created” at a certain time, spacelessness and timelessness existed before this “creation.” The One Who created these concepts is Allah, Who is utterly exalted above them and, consequently, Everlasting. This fact never changes, for only He has genuine existence. Outside His existence, everything is mortal and doomed to perish. As the Qur'an informs us, the only Truth is Him:
High exalted be Allah, the King, the Real! Do not rush ahead with the Qur'an before its revelation to you is complete, and say: “My Lord, increase me in knowledge.” (Surah Ta Ha, 20:114)
That is because Allah is the Real, gives life to the dead, and has power over all things. (Surat al-Hajj, 22:6)In that situation the only protection is from Allah, the Real. He gives the best reward and the best outcome. (Surat al-Kahf, 18:44)
“You are the Truth, Your saying is the Truth, Your promise is the Truth, and the meeting with You is the Truth, and Paradise is the Truth, and the (Hell) Fire is the Truth." (Sahih Bukhari)