Old priest with the heartless description of the chosen people (5)
I believe the answer is:
elite
'the chosen people' is the definition.
(thesaurus)
'old priest with the heartless' is the wordplay.
'old priest' becomes 'eli' (Biblical character).
'with' means one lot of letters go next to another.
'heartless' suggests removing the centre.
'the' with its middle removed is 'te'.
'eli'+'te'='ELITE'
'description of' is the link.
This may not be correct. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for elite that I've seen before include "Pick of the bunch" , "top drawer?" , "Aristocratic" , "Exclusive group" , "Group enjoying superior status" .)