>>5927725
Alright I'll explain in Reddit spacing.
The scene is right after Valeria and Akiro fights off the spirits that have come to forcibly take Conan to the underworld when performing the healing ritual (in exchange Valeria is fated to die in his place).
The entire plot of the movie revolves around 'The Riddle of Steel' a kind of meditation on life. His father told him you can always trust a good sword and then Thulsa Doom kills his family with it. Conan struggles and rises to every occasion forging himself into an instrument of revenge, when he next encounters Thulsa he can't even remember who Conan is or why anyone would waste their life on something so trivial.
Thulsa then even spoonfeeds his interpretation of The Riddle of Steel as it's commonly understood by those who have walked the path stating that flesh is stronger, a sword cannot swing itself. Then proclaims his superiority by showing that he can control the flesh of others and orders one of the cultists to jump to their death.
Having been utterly crushed and defeated he's tortured on the Tree of Woe before being rescued by his companions, but he's so wounded he will die without divine intervention which brings us to this scene. He was so convinced he could enact his revenge because he had everything on his side, his physical prowess even morality. Here he is both contemplating his own mortality and strength by performing the kata he learned from the eastern swordmasters in his youth but resolves to push forth despite his own doubts.
I'll skip ahead but in the final confrontation Thulsa attempts to seduce/hypnotize (he's a kind of snake demigod) and says that he is the one who shaped him into the man he is today and is more of a father to him than anyone. Conan manages to break the spell and decapitates him with his father's broken sword. After this Conan sits in contemplation at the Ziggurat realizing that if flesh wields the sword then it is will that moves the flesh. Very Nietzschean.
