“battle against sin” aka ‘battling for his soul’ is battling in the arena of the flesh dynamics and spirit dynamics.
Our role is not to fix ‘sin’ – Christ has already “fix it” on the Cross.
Our role is to release the goodness that is within him (the new heart that is given to him when he receives Jesus into his life). Christ has come to give life, and life in abundance. The resurrected life!
I think viewing the battle this way helps us to listen better and be quiet. If we have this view, we will not be quick to try to fix the other person, give them advice, or give them comforting words. It will lead us to be totally dependent on the Holy Spirit.
It will also allow us to lead the other person to life in Jesus and not death in the desert of trying harder.
Cooperating with the Holy Spirit to release what God has already placed in a person, is the goal of providing spiritual direction. It’s not something a person does to another person, it’s watching God work with what he already put in place and the response of the other person to except that love and truth.