The most common and most likely answer to this crossword clue is the 6 letter word BUDDHA
I've seen this crossword clue in The Times
B
U
D
D
H
A
More clues leading to the result BUDDHA
- Spiritual teacher with friend had nuts
- Friend had upset spiritual leader
- Teacher and doctor had to support American pal
- Pal had reincarnated spiritual leader …
- New growth had damaged idol
- Sign of new life had excited man of faith
- Shoot upsetting advert around hospital with religious figure
- Old teacher had trouble following friend
- Rewound tape had back-to-front leader
- Controversial tome this one revered could be badmouthed
Buddy explains!
The straight part
We know that "sage" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case sage = buddha.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.