What we do makes us who we are.
In his Theological Reflection in the Church of England's Guidelines to the professional conduct of the clergy (Church House Publishing 2015)  The Very Revd Dr Francis Bridger writes: 
According to William Willimon, character can be defined as the ‘basic moral orientation that gives unity, definition and direction to our lives by forming our habits into meaningful and predictable patterns that have been determined by our dominant convictions’.
What we do is governed by who we are.
As Stanley Hauerwas notes, each of us makes moral choices arising out of ‘the dispositions, experience, traditions, heritage and virtues that he or she has cultivated’. 
This paragraph setting is not in the text as used in Church of England  but as borrowed by the Church in Wales on its website page Introduction to the Cure of Souls.
Here this sentence is made its own paragraph:
        What we do is governed by who we are.
But this is not, in fact, as true as it might seem.
We may have to travel a long way through life before we begin to realize that the opposite is in fact the case.
Surely, we might argue, it is obviously the right thing to say that "What we do is governed by who we are."
But the truth is the reverse: what we do makes us who we are and shapes our thoughts and ideas.
It would be easy to say it's a circular thing and that it is true that both action and thought influence each other.
But that would be to miss the point. 
Insisting that what we do makes us who we are is counter intuitive only so long as our intuition is governed by the obvious. Obviously we have attitudes and they make us do things.
But that does not describe how we learned from our infancy. It was how we behaved, behaviour largely shaped by parental figures, that made us who we are.  And it is still true that who we are is shaped by what we do.  We act our way into making our mind up, we behave our way into being who we are. It is this counter intuitive approach to pedagogy that marks out Jesus' life. He told stories about how to act, he never taught doctrinal ideas. 
For Jesus we learn what forgiveness is by forgiving. We learn what generosity is by being generous, we learn what love is by acting lovingly. This is how infants learn, and in truth how we learn the truly deep things right through our lives.
And that is the difference between virtue and moral values.
Virtues are not ideas but practices, values are not practices but ideas.
So the "theological virtues" - faith, hope and love - are not ideals or mental concepts but ways of behaving or they are nothing at all.
Dr Bridger's essay is thus sending us off on the reciprocal track to the one we should be on. A theology of Christian living that starts with "who we are" will have limited success in changing who we are and little hope at all of helping us grow our souls, that is, growing in holiness and growing up into Christ.
Only by practicing virtue will we allow our minds to be renewed.
St Paul writes: Do not be conformed to this world but be transformed by the renewal of your mind, that you may prove what is the will of God, what is good and acceptable and perfect. 
Romans 12:2
That appears to suggest we start with the renewal of our minds.
But in the verse before he says this:
I appeal to you therefore, brothers and sisters, by the mercies of God, to present your bodies as a living sacrifice, holy and acceptable to God, which is your spiritual worship. Romans 12:1
Renewal starts with the body, with what we do. And what we do is worship, the persistent act of prayer and praise, of making space in our hearts for God, so that our minds can follow and be transformed by their renewal.
This is how we grow our souls. When we stick at our daily prayers, when we are faithfully present at the Eucharist, when we lift our hearts and give praise, even when our minds are  wanting to do something else. It is in the doing that we are remade and that is how our souls grow.
This truth has many implications. One of those implications is that signing up to a correct statement of belief means very little. Signing up to prayer and praise means everything. This is what the Letter of James is all about, of course.
If this seems nonsense to you, well fair enough. I suspect it would have seemed nonsense to me until a certain point in my life and when I had experienced a set of life events and crisis points. But maybe you don't need to be dragged through the mud, but just let go of your ideas and do the one thing needful. Sit quietly, pray and praise. And God will start to do the rest, and will expect us to join in. Because it's not any activity God is asking of us, but this activity. What we do makes us who we are.