What is here called interiority in English, is interioridad in Spanish, and interiorita in Italian.
Interiority refers to the interior life, a particular lived reality of a spiritual tradition (in Italian, spiritualita). It is a spiritual withdrawing inwards in order to come to a better knowledge of both oneself and God. This is our "resting in God." As the opening paragraph of the Confessions of Augustine acknowledges, "You have made us for yourself, O Lord, and our hearts are restless until they rest in you." (Confessions, 1,1.) Only in God is found the final happiness of any person.
By way of the interior life we are capable of knowing and loving God. In the perception of Augustine, this requires our going into ourselves, of making perfect the heart so that with uninterrupted desire we may arrive at god. "Do not look outside; return to yourself. In our interior the truth resides.. Go inside, where the light of reason is illumined." (Augustine, The True Religion 39,72) And, again, Augustine advised, "Enter, then, into your heart (Isaiah 46:8) and if you have faith, you will find Christ there. There Christ speaks to you. I must use my voice, but he instructs you more effectively in silence." For Augustine, interiority was not only a means of approach of God. For Augustine, interiority – or inwardness – is actually three layers of ideas. Firstly and most simply, it is personal inward space (Confessions 10, 17). Secondly, it is inward personal revelation or illumination. Thereby a person within this inner space experiences restlessness (spiritual unease) in searching for God. This was the theological task that Augustine undertook in writing his Confessions (7, 10) Thirdly, Augustine suggests that external words and sacraments are outward signs that express realities within a person. They can bring about within the soul the world of eternal truth
In De Magistro ("About the Teacher") Augustine wrote that no teacher on earth except Christ could instruct in the eternal truth, which came directly through divine illumination. Interiority was so important for Augustine, therefore, because is showed where a person made contact with God. The external created world of words and sacrament pointed to an interior world that was more valuable and "real" in the context of eternity – more so than the external world of the city of man. More broadly again, interiority was the theme most known in the anthropology of Augustine, the way a person to use his or her own basic human nature most profitably as God intended.
Interiority denoted a search of the heart, of the interior of self, of the very consciousness of a person. In another place, Augustine said that Jesus is our interior master, or "the master within us." In order to hear and understand Him, we need to develop an atmosphere of attentive inner silence when we seek to go deeper into ourselves along the way of interior prayer. In a pair of beautiful images, Augustine said that we must develop the eyes and ears of our heart so as to see and hear what Christ wishes to communicate to us. To achieve this, we must also purify the eyes of the heart so that we will be able to see God. Through this retiring into oneself, Augustine came to a deeper awareness or consciousness both of himself and of the mystery of God. Interiority (interioridad in Spanish, and interiorita in Italian) means withdrawing inwards spiritually in order to meet God. It can be seen as our "resting in God." Interiority is a fundamental shift of thinking which holds that truth may be found through a self-exploration of the inner life of an individual person. It is an insight that largely was prompted within the Christian church Augustine.
We think that "going within oneself" psychologically or spiritually is an obvious movement when wishing to move away from daily cares. It is common to think that one can free oneself from the exterior constraints by moving towards a voice within ourselves. If this appears to us as an obvious step, we are thinking in a way that the people in the time of Augustine did not generally adopt.
Following the thought of Plotinus, the second-century pagan Roman philosopher, Augustine in his On True Religion urged his readers, "Do not go outward; return within yourself. In the inward person dwells truth." (cf. On True Religion 39,72) To Augustine, interiority meant the search of the heart, of the interior of oneself, of the life and consciousness within the self. It is a moving towards the voice within ourselves. Augustine considered that, since people were created in the image of God and with an immediate tendency toward Him, our dignity consists in being the more like God (On the Trinity 12,11,16).
Yet it is clear to him that not everyone was yet aware of the fact that every human being is capable of God and thus can reach God. In order to overcome this unawareness, Augustine proposed the way of interiority, that is the turning away from the physical to the spiritual world, from the outer world to the inner self (cf. Confessions 10,6,8-7,11). For Augustine spirituality implied the entering into the depths of oneself, (Confessions 7,10,16) where one comes to terms with his soul, which "is created in the image and likeness of God." (On the Trinity 14,4,6) Thus in his Confessions he regretted his own obstinate nature and slowness in embracing this reality. "I searched for you outside myself, while all along you were within me. You were in me, but I was not in You…" he regretted his own obstinate nature and slowness in embracing this reality. "I searched for you outside myself, while all along you were within me. You were in me, but I was not in You…" Interiority became the method by which Augustine communicated intimately with God.
Interiority, as understood by Augustine, is an exercise of coming to know both oneself and God. Thus self-knowledge is the crucial first step toward knowledge of God (see Soliloquies 1,9,16). Hence Augustine could include in his Confessions the prayerful words, "Lord, let me know myself, and let me know You." Augustine regarded interiority as a human effort under the assistance of God. He was successful in this regard. He wrote, "And spurred on by the method to return to myself, I entered into my deepest interior, led by You. There I was in a state such that You became my helper. I entered and looking with my mind's eye - how weak it is - I saw above this eye, above my spirit a constant light." (Confessions 7, 10, 16) He also wrote, "Being admonished by all of this to return to myself, O Lord, I entered my own depths with you as my guide, and I was able to do it because you were my helper." (Confessions 7, 10, 16) In his Confessions he regretted his own stubborn nature and slowness in embracing this reality. "I searched for you outside myself, while all along you were within me. You were in me, but I was not in You…"
The quest for interiority leads to the contemplation of God himself. Interiority, as understood by Augustine, is an exercise of coming to know both oneself and God. Thus self-knowledge is the crucial first step toward knowledge of God (Soliloquies 1,9,16), such that Augustine could include in his Confessions the prayer, "Lord, let me know myself, and let me know You." the prayer, "Lord, let me know myself, and let me know You."
For Augustine the encounter with God is an interior process. It is a method of introversion that is preceded by a time of clearing the mind of all sensual images in order that it may see itself and know itself. The purpose of this searching within the self is not an interior exercise of the psychological examination of self. It is undertaken as a movement which opens up the individual. One goes inward as a sure way of going where God can be met. This does not mean a brief examination of self, but that the whole self becomes the subject of reflection. This leads to a deeper awareness of consciousness, a stronger consideration of the basic tenets of morality, and a more realistic understanding of the ignorance of an individual person in relation to the infinite realm of the mysteries of God and of all that God created. Interiority thus became the way through which Augustine communicated with God.