Push gist of argument (6)

I believe the answer is:
thrust
This clue could be a double definition.
'push' is the first definition.
(synonyms)
'gist of argument' is the second definition.
'thrust' can be an answer for 'gist' (thrust/gist of an argument). I am not sure about the 'of argument' bit.
Can you help me to learn more?
(Other definitions for thrust that I've seen before include "Push forward with truths" , "Shove forward" , "Push forward, as fencer does sword" , "Lunge forward" , "Push suddenly forward" .)
