Young Earth Creationism (YEC) is the Christian dogma which teaches that, in six days, God created the heavens and the earth— man.
Since the beginning of the revelation of God to man, this doctrine has been held as part of necessary belief, being taught to us by, both, the Prophets and the Apostles. And, just as with all things essential in our faith, these have been passed down through the apostolic lines, unto the Church Fathers, and until today. So, let’s take a look at what they said, about YEC.
“They are deceived by those highly mendacious documents which profess to give the history of many thousand years. Though, reckoning by the sacred writings, we find that not even 6,000 years have yet passed.”
“According to Scripture, less than 6,000 years have elapsed since [man] began to be.”
“Celsus, from a secret desire to cast discredit upon the Mosaic account of the creation, which teaches that the world is not yet ten thousand years old, but very much under that, while concealing his wish, intimates his agreement with those who hold that the world is uncreated.”
“And there was evening and there was morning: one day. And the evening and the morning were one day . . . Now twenty-four hours fill up the space of one day—we mean of a day and of a night . . . It is as though it said: twenty-four hours measure the space of a day, or that, in reality a day is the time that the heavens starting from one point take to return there.”
“In as many days as this world was made, in so many thousand years shall it be concluded. And for this reason the Scripture says: ‘Thus the heaven and the earth were finished, and all their adornment. And God brought to a conclusion upon the sixth day the works that He had made; and God rested upon the seventh day from all His works.’ This is an account of the things formerly created, as also it is a prophecy of what is to come. For the day of the Lord is as a thousand years; and in six days created things were completed: it is evident, therefore, that they will come to an end at the sixth thousand year.”
“All the years from the creation of the world, [until now], amount to a total of 5,698 years.”
Man, O Death, despise it not, that image of Adam: which like a seed is committed to earth, till the Resurrection. To you be glory Who descended and plunge, after Adam: and draw him out from the depths of Sheol, and bring him into Eden! Death, I marvel at this seed, and at your words: for lo! After five thousand years, it springs not yet.
“Scripture established a law that twenty-four hours, including both day and night, should be given the name of day only, as if one were to say the length of one day is twenty-four hours in extent.”
“Therefore let the philosophers, who enumerate thousands of ages from the beginning of the world, know that the six thousandth year is not yet completed . . . God completed the world and this admirable work of nature in six days, as is contained in the secrets of Holy Scripture, and consecrated the seventh day, on which He rested from His works.”
Though not an Orthodox Christian church father, Aquinas is believed to be an exceedingly great theologian and philosopher, by Romans Catholics and some Protestants. Here's what he taught:
”Thus we find it said at first that ‘He called the light Day’: for the reason that, later on, a period of twenty-four hours is also called ‘day,’ where it is said that ‘there was evening and morning, one day.’”
Though not a church father, Josephus— a Orthodox Jewish scholar from the first century— was cited by many church historians and saints. He says the following:
“In just six days, the world, and all that is therein, was made.”