Haecceitas

"A tree gives glory to God by being a tree. For in being what God means it to be it is obeying Him. It 'consents' so to speak, to his creative love. It is expressing an idea which is in God and which is not distinct from the essence of God, and therefore a tree imitates God by being a tree.
The more a tree is like itself, the more it is like Him… It it tried to be something else which it was never intended to be, it would be less like God and therefore it would give him less glory
No two created beings are exactly alike. And their individuality is no imperfection. On the contrary, the perfection of each created thing is not merely in its conformity to an abstract type but in its own individual identity with itself. 

This particular tree will give glory to God by spreading out its roots in the earth and raising its branches into the air and the light in a way that no other tree before or after it ever did or will do…. 

For me to be a saint means to be myself. Therefore the problem of sanctity and salvation is in fact the problem of finding out who I am and of discovering my true self. 

Trees and animals have no problem. God makes them what they are without consulting them, and they are perfectly satisfied. 

With us it is different. God leaves us free to be whatever we like. We can be ourselves or not, as we please. We are at liberty to be real, or to be unreal. We may be true or false, the choice is ours. We may wear now one mask and now another, and never, if we so desire, appear with our own true face. But we cannot make these choices with impunity. Causes have effects, and if we lie to ourselves and to others, then we cannot expect to find truth and reality whenever we happen to want them. If we have chosen the way of falsity we must not be surprised that truth eludes us when we finally come to need it! 

Our vocation is not simply to be, but to work together with God in the creation of our own life, our own identity, our own destiny….

The seeds that are planted in my liberty at every moment, by God's will, are the seeds of my own identity, my own reality, my own happiness, my own sanctity…."

Thomas Merton: Seeds of Contemplation

Or, to put it another way ..... 

"As kingfishers catch fire, dragonflies draw flame;
As tumbled over rim in roundy wells
Stones ring; like each tucked string tells, each hung bell's
Bow swung finds tongue to fling out broad its name;
Each mortal thing does one thing and the same:
Deals out that being indoors each one dwells;
Selves — goes itself; myself it speaks and spells,
Crying Whát I dó is me: for that I came.

I say móre: the just man justices;
Keeps grace: thát keeps all his goings graces;
Acts in God's eye what in God's eye he is —
Chríst — for Christ plays in ten thousand places,
Lovely in limbs, and lovely in eyes not his
To the Father through the features of men's faces."

Gerard Manley Hopkins