Should Genesis 1:2 be translated "And the earth became without form..."? 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 was became 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.


Is this a sound translation? Why is was the more usual one?
The Hebrew verb "was" is in the Qal (indicative) perfect tense.   "Became" is a fanciful translation.  There's nothing wrong with fanciful translations and midrasch.  But it's probably best to avoid basing tonnage of doctrine on midrasch or fancy.

There is an ambiguity in Hebrew about past or future actions, but that crops up when the IMperfect tense is used, not the perfect.