Being of One Mind is not the same as being single-minded.
A single-minded person is not consciously aware of their ability to choose their own life path.
They are steadfast in their belief that what they have been taught is right.
When I am of One Mind, all aspects of my mind co-operate in unison.
When all aspects of my mind are working together, they align with the Universal Mind.
When my sub-conscious, conscious & super-conscious mind are all aligned, I am in harmony with my supra-conscious Universe.
The supra-conscious universal mind is One Version of all Consciousness.
In absolute reality there is only one Mind.
In relative dual reality, my perspective of the world is relative to the conscious-awareness of my ego Self.
I can be single-minded, I can be in two minds or I can be of One Mind that is the perspective of my Soul.