Your most subtle and deadly adversary

I asked a scholar the meaning of the tradition which
says, ‘Your most subtle and deadly adversary is the
sexual energy in your loins.’ ‘The reason is this,’ he
answered. ‘Any ordinary enemy that you treat politely
will begin to be your friend, except that lust-energy.
The more you indulge and placate that, the more
powerfully it drags you both down. Strong discipline
needs to be brought forward to stop that bully from
killing you.’

[Saadi {Abū-Muhammad Muslih al-Dīn bin Abdallāh Shīrāzī}, ‘I Asked a Scholar’ (trans. by Coleman Barks)]