Holiness is twofold... At first it is effort, then a gift. In other words, if you strive to be holy, you are eventually endowed with holiness. The effort consists in separating and removing yourself from the material aspect of things and linking yourself with the divine...
But it is impossible to attain this state on your own.
After all, you are physical -- flesh and blood.
So ultimately, holiness is a gift.
What you can do is strive to pursue true knowledge.
Be persistent in learning how to sanctify what you do.
In the end, the Blessed Holy One will guide you on the path
that it wishes and impart holiness to you, so that you become holy.
Then you will succeed, attaining union continuously.
(p. 158)