Is the Genesis creation account consistent with the Big Bang theory according to Catholic theology? I'm doing some research and am trying to determine whether the creation story of Genesis, chapter 1 (7 days-let there be light) is consistent with the Big Bang Theory. I am finding sources that contradict one another. I'd like to know if the Genesis story of creation is consistent with the Big bang theory solely from a Catholic point of view.
The Catechism of the Catholic Church has

289 Among all the Scriptural texts about creation, the first three chapters of Genesis occupy a unique place. From a literary standpoint these texts may have had diverse sources. the inspired authors have placed them at the beginning of Scripture to express in their solemn language the truths of creation — its origin and its end in God, its order and goodness, the vocation of man, and finally the drama of sin and the hope of salvation. Read in the light of Christ, within the unity of Sacred Scripture and in the living Tradition of the Church, these texts remain the principal source for catechesis on the mysteries of the &quot;beginning&quot;: creation, fall, and promise of salvation.
290 &quot;In the beginning God created the heavens and the earth&quot;:128 three things are affirmed in these first words of Scripture: the eternal God gave a beginning to all that exists outside of himself; he alone is Creator (the verb &quot;create&quot; — Hebrew bara — always has God for its subject). the totality of what exists (expressed by the formula &quot;the heavens and the earth&quot;) depends on the One who gives it being.
295 We believe that God created the world according to his wisdom.141 It is not the product of any necessity whatever, nor of blind fate or chance. We believe that it proceeds from God's free will; he wanted to make his creatures share in his being, wisdom and goodness: &quot;For you created all things, and by your will they existed and were created.&quot;142 Therefore the Psalmist exclaims: &quot;O LORD, how manifold are your works! In wisdom you have made them all&quot;; and &quot;The LORD is good to all, and his compassion is over all that he has made.&quot;143 God creates &quot;out of nothing&quot;.
296 We believe that God needs no pre-existent thing or any help in order to create, nor is creation any sort of necessary emanation from the divine substance.144 God creates freely &quot;out of nothing&quot;.145

Thus it may be seen that Catholic teaching, expressed in the Catechism, does not depend on the literal truth (or not) of Genesis 1. Other than a few brief words of literary analysis, it expresses no opinion — although St Augustine of Hippo certainly did. What is important is that Genesis 1 testifies that God created all that exists, and did so from nothing.
Although God is continually revealing himself and his methods, scientists have not reached the origin of creation, either by observation of the deep universe or by theoretical calculation. Even if one posits that the Big Bang was the means by which creation was effected, it is thought that everything emanated from a singularity: a point of infinite density and zero size — nothing.

128: Gen 1.1
141: Cf Wis 9:9
142: Rev 4:11
143: Pss 104:24; 145:9
144: Cf Dei Filius, cann 2–4 (1869)
145: Lateran Council IV (1215)