Chapel in speculation facing endless perdition (6)
I believe the answer is:
'chapel' is the definition.
(I've seen this before)
'speculation facing endless perdition' is the wordplay.
'speculation' becomes 'bet' (bet is a kind of speculation).
'facing' means one lot of letters go next to another.
'endless' means to remove the last letter.
'perdition' becomes 'hell' (synonyms).
'hell' with its last letter taken away is 'hel'.
'in' acts as a link.
(Other definitions for bethel that I've seen before include "Methodist or Baptist church; church for seamen" , "Chapel" .)