It's [*de fide*][2], a truth of the Catholic faith, that God created the universe a finite time in the past and that the universe will end a finite time into the future. Thinking the universe is eternal is a [heresy][1].

The Fourth Lateran Council pronounced ([Denzinger 4][3]28-9):

>Firmly we believe and we confess simply that the true God […] by His own omnipotent power at once from **the beginning of time** created each creature from nothing

and that He will 

>come at **the end of time**, to judge the living and the dead

Scriptural proofs ([*Fundamentals of Catholic Dogma*][4] bk. 2, ch. 1, §6, 1.):

>[John 17:5][5]: “And now glorify thou me, O Father, with thyself, with the glory which I had before the world was with thee.” [Eph. 1:4][6]: “He chose us in Him (Christ) even before the foundation of the world.” [Ps. 101:26][7]: “In the beginning, O Lord, thou foundest the earth.” Cf. [Gn. 1:1][8]; [Pro. 8:22][9] et seq.; [Ps. 89:2][10]; [John 17:24][5].

St. Thomas Aquinas defended this Catholic truth, against those (e.g., the Greeks, Aristotle) who believed the universe to be eternal, in his short work [*De aeternitate mundi* (*On the Eternity of the World*)][11]. He argues this truth can only be known by divine revelation.


  [1]: https://www.catholicculture.org/culture/library/dictionary/index.cfm?id=33902
  [2]: https://www.catholicculture.org/culture/library/dictionary/index.cfm?id=32992
  [3]: http://patristica.net/denzinger/#n400
  [4]: https://isidore.co/calibre/#panel=book_details&book_id=7262
  [5]: http://drbo.org/cgi-bin/d?b=drl&bk=50&ch=17&l=5-#x
  [6]: http://drbo.org/cgi-bin/d?b=drl&bk=56&ch=1&l=4-#x
  [7]: http://drbo.org/cgi-bin/d?b=drl&bk=21&ch=101&l=26-#x
  [8]: http://drbo.org/cgi-bin/d?b=drl&bk=1&ch=1&l=1-#x
  [9]: http://drbo.org/cgi-bin/d?b=drl&bk=22&ch=8&l=22-#x
  [10]: http://drbo.org/cgi-bin/d?b=drl&bk=21&ch=89&l=2-#x
  [11]: https://isidore.co/aquinas/DeEternitateMundi.htm