I know you have solved this, but this is my rationale.
The _most likely_ solution is that it is a transcription error, and Matthew's surname should have been transcribed as Moore. As it is so easy to check the original record on this one, do not rely on FamilySearch's transcription. You can view the original entry here on FamilySearch.
So clearly not a transcription error. However...
Checking the original record reveals a key piece of information not on the transcription you were relying on. Rebecca was a **widow**.
You can now revise your most likely solution - this was Rebecca's second marriage. You can now commence research, knowing that Rebecca was probably born a Lark, and first married a Moore.