Question: How would you reconcile Matthew 19:4 and Mark 10:6 with the premise that Earth is billions of years old? I believe the human race has only been around for about 6,000 years.
Answer: I would agree with you, in part. According to the genealogies and historical facts given in the Bible, Adam and Eve were created approximately 6,000 years ago. They were created on Day Six of the remodeling of Earth to make it fit for man’s habitation. This begins in the last half of Genesis 1:2,
“...And the Spirit of God moved on the face of the waters.”
We do not know how long the Earth lay in the judgment of the first half of Genesis 1:2,
“And the earth was without form and void; and darkness was upon the face of the deep.”
(Looking at the sentence structure of the Hebrew, a better translation is “Now the earth had become without form and void...”)
The verses you ask about are part of a context in which our Lord is being tested by the Pharisees on the subject of divorce. It is found both in Matthew and Mark. We will quote the verses:
“But from the beginning of the creation God made them male and female.” - Mark 10:6
“...Have ye not read, that he that made them at the beginning made them male and female.” - Matthew 19:4
What does the Scripture mean by the “beginning of the creation?” Does it mean from Genesis 1:1; or does it mean from the creation of Adam and Eve, i.e. the human race? The word “creation” is “ktisis” in the Greek, “the act of founding, establishing, building, etc.” What God is talking about here is the foundation; or establishing of the human race, “male and female.” The word “beginning” in both verses comes from the Greek word “arche” or “the beginning, origin, the first person that commences, the first person or thing in a series, the leader...” In other words, the first people in the human race, Adam and Eve.
Christ is simply saying that from the beginning of the human race, God did not intend for men and women, once married, to divorce. Then he quotes Genesis 2:24 in Matthew 19:5,
“Therefore shall a man leave his father and his mother, and shall cleave unto his wife: and they shall be one flesh.”
This is not a proof that the Earth is only 6,000 years old. The Bible is an inspired record of God’s dealings with man. It begins with man and ends with man.