Filled the grid, got the 11 letter theme-word, the 3 surplus answers and can see a couple of 3 letter religious text abbreviations (but no more than a couple!). Stumped. Would appreciate a nudge in the right direction.
Once you find one you'll know that its symmetrically placed entry will have another - e.g there's one in the first down clue and another in the last down entry.
Starting in top row - first, sixth and eighth columns and the corresponding symmetrical placed ones finishing in the bottom row; the two ten letter entries.