Question:
Do you believe in the “Gap Theory”?

Answer:

The “Gap Theory” says that the account of the creation in Genesis, chapter one, is really a re-creation…back to the original state the world was created. Genesis 1:1,2: “In the beginning God created the heaven and the earth. And the earth was without form, and void; and darkness was upon the face of the deep. And the Spirit of God moved upon the face of the waters.” In the phrase, “was without form,” the word ‘was’ can be correctly translated ‘became.’ So, it appears that the world was not created without form, but came to be without form. 

Isaiah 45:18: “For thus saith the LORD that created the heavens; God Himself that formed the earth and made it; He hath established it, He created it not in vain, He formed it to be inhabited: I am the LORD; and there is none else.” In this verse in Isaiah the word “vain” is the same Hebrew word as “without form” in Genesis 1:2. This teaches us that although the world was without form, that is not the way the Lord created it. He formed it to be inhabited.

So … the “Gap Theory” says there is an undetermined amount of time between Genesis 1:1, and Genesis 1:2. “God created the heaven and the earth” … and it was perfect.  Something happened, and it became “without form.”  Some teach that this is when Lucifer was cast down from his position in Heaven. The six days of creation is when the Lord established order for His creation.

You asked if I believe in the Gap Theory. Yes, I do. However, I would not be dogmatic and try to force my thoughts on this matter on someone else. This issue is not significant enough, or brought out in Scripture clearly enough to become a matter of contention.