The Gap theory seems to be based largely on translating Genesis 1:2 differently from the usual translations, eg. KJV:
1:1 In the beginning God created the heaven and the earth.
1:2 And the earth
becamewithout form, and void; and darkness was upon the face of the deep. And the Spirit of God moved upon the face of the waters.
Is this a sound translation? Why is
was the more usual one?