The spiritual battlefield is definitely one of the mind.
It is in the mind where decisions for eternity are made.
There are numerous verses about developing the mind of Christ. Think about that. Our mindset will lead us to either receive the seal of God or the mark of the beast.
Where is your mindset leading you today?
Rom 12: 1,2
1 Pet 2:5
Rom 8:6,7, 14
1 Jn 4:4