This passage is from the first chapter of one of my textbooks for this semester (An Introduction to the Trinity by Declan Marmion and Rik Van Nieuwehove):
For its part, theology has an ‘existential’ and practical aspect; to do theology implies some form of faith-experience which serves as a foundation for reflection. In the patristic era, theology was not solely intellectual, but also a spiritual activity, an affaire d’amour, inseparable from prayer. Philosophy and theology often served as synonyms for theoria or contemplation. The Greek philosophers comprehended things ‘with their eyes’ (Gk theorein = to look at). They ‘theorised’ in the literal sense of the word. We arrive at understanding through participation, through uniting with the object – a way of perceiving that transforms the perceiver, not what is perceived. Perception confers communion: we know in order to participate, not in order to dominate. Knowledge, then, is an act of love: we can only know to the extent to which we are capable of loving what we see, and are able, in love, to let it be wholly itself.
I think this is also one of the reasons why it can be difficult to completely open up in prayer, because we may walk away somewhat changed, and that frightens us.