Objection 1. It would seem that there was no faith, either in the angels, or in man, in their original state. For Hugh St. Victor says in his Sentences (De Sacram. i, 10) that "man cannot see God or things that are in God, because he closes his eyes to contemplation." Now the angels, in their original state, before they were either confirmed in grace, or had fallen from it, had their eyes opened to contemplation, since "they saw things in the Word," according to Augustine (Gen. ad lit. ii, 8). Likewise the first man, while in the state of innocence, seemingly had his eyes open to contemplation; for Hugh St. Victor says (De Sacram. i, 6) that "in his original state man knew his Creator, not by the mere outward perception of hearing, but by inward inspiration, not as now believers seek an absent God by faith, but by seeing Him clearly present to their contemplation." Therefore there was no faith in the angels and man in their original state.
Objection 2. Further, the knowledge of faith is dark and obscure, according to 1 Corinthians 13:13: "We see now through a glass in a dark manner." Now in their original state there was not obscurity either in the angels or in man, because it is a punishment of sin. Therefore there could be no faith in the angels or in man, in their original state.
Objection 3. Further, the Apostle says (Romans 10:17) that "faith... cometh by hearing." Now this could not apply to angels and man in their original state; for then they could not hear anything from another. Therefore, in that state, there was no faith either in man or in the angels.
On the contrary, It is written (Hebrews 11:6): "He that cometh to God, must believe." Now the original state of angels and man was one of approach to God. Therefore they had need of faith.
I answer that, Some say that there was no faith in the angels before they were confirmed in grace or fell from it, and in man before he sinned, by reason of the manifest contemplation that they had of Divine things. Since, however, "faith is the evidence of things that appear not," according to the Apostle (Hebrews 11:2), and since "by faith we believe what we see not," according to Augustine (Tract. xl in Joan.; QQ. Evang. ii, qu. 39), that manifestation alone excludes faith, which renders apparent or seen the principal object of faith. Now the principal object of faith is the First Truth, the sight of which gives the happiness of heaven and takes the place of faith. Consequently, as the angels before their confirmation in grace, and man before sin, did not possess the happiness whereby God is seen in His Essence, it is evident that the knowledge they possessed was not such as to exclude faith.
It follows then, that the absence of faith in them could only be explained by their being altogether ignorant of the object of faith. And if man and the angels were created in a purely natural state, as some [St. Bonaventure, Sent. ii, D, 29 hold, perhaps one might hold that there was no faith in the angels before their confirmation in grace, or in man before sin, because the knowledge of faith surpasses not only a man's but even an angel's natural knowledge about God.
Since, however, we stated in I, 62, 3; I, 95, 1 that man and the angels were created with the gift of grace, we must needs say that there was in them a certain beginning of hoped-for happiness, by reason of grace received but not yet consummated, which happiness was begun in their will by hope and charity, and in the intellect by faith, as stated above (Question 4, Article 7). Consequently we must hold that the angels had faith before they were confirmed, and man, before he sinned. Nevertheless we must observe that in the object of faith, there is something formal, as it were, namely the First Truth surpassing all the natural knowledge of a creature, and something material, namely, the thing to which we assent while adhering to the First Truth. With regard to the former, before obtaining the happiness to come, faith is common to all who have knowledge of God, by adhering to the First Truth: whereas with regard to the things which are proposed as the material object of faith, some are believed by one, and known manifestly by another, even in the present state, as we have shown above (1, 5; 2, 4, ad 2). In this respect, too, it may be said that the angels before being confirmed, and man, before sin, possessed manifest knowledge about certain points in the Divine mysteries, which now we cannot know except by believing them.
Reply to Objection 1. Although the words of Hugh of St. Victor are those of a master, and have the force of an authority, yet it may be said that the contemplation which removes the need of faith is heavenly contemplation, whereby the supernatural truth is seen in its essence. Now the angels did not possess this contemplation before they were confirmed, nor did man before he sinned: yet their contemplation was of a higher order than ours, for by its means they approached nearer to God, and had manifest knowledge of more of the Divine effects and mysteries than we can have knowledge of. Hence faith was not in them so that they sought an absent God as we seek Him: since by the light of wisdom He was more present to them than He is to us, although He was not so present to them as He is to the Blessed by the light of glory.
Reply to Objection 2. There was no darkness of sin or punishment in the original state of man and the angels, but there was a certain natural obscurity in the human and angelic intellect, in so far as every creature is darkness in comparison with the immensity of the Divine light: and this obscurity suffices for faith.
Reply to Objection 3. In the original state there was no hearing anything from man speaking outwardly, but there was from God inspiring inwardly: thus the prophets heard, as expressed by the Psalm 84:9: "I will hear what the Lord God will speak in me."
Source: Summa Theologica (New Advent)