Irenaeus - Adv. Her. 4.39.2 How, then, shall he be a God, who has not as yet been made a man? Or how can he be perfect who was but lately created? How, again can he be immortal, who in his mortal nature did not obey his Maker? For it must be that thou, at the outset, shouldest hold the rank of a man, and then afterwards partake of the glory of God. For thou dost not make God, but God thee. If, then, thou art God’s workmanship, await the hand of the Maker which creates everything in due time; in due time as far as thou art concerned, whose creation is being carried out.(ANF 1.522-523).
Irenaeus - Adv. Her. 5.Pref …the Word of God, our Lord Jesus Christ, who did, through His transcendent love, become what we are, that He might bring us to be even what He is Himself.(ANF 1.526).
Theophilus - To Autolycus 27 Was man made by nature mortal? Certainly not. Was he, then, immortal? Neither do we affirm this. …He was by nature neither mortal nor immortal. For if He had made him immortal from the beginning, He would have made him God. … keeping the commandment of God, he should receive as a reward from Him immortality, and should become God.(ANF 2.105).
Clement of Alexandria - Exhortation 1 …the Word of God became man, that thou mayest learn from man how man may become God.(ANF 2.174).
Clement of Alexandria - The Instructor 3.1 It is then, as appears, the greatest of al lessons to know one’s self. For if one know himself, he will know God; and knowing God, he will be made like God…But that man with whom the Word dwells does not alter himself, does not get himself up: he has the form which is of the Word; he is made like to God…and that man becomes God, since God so wills. Heraclitus, then, rightly said, “Men are gods, and gods are men.”(ANF 2.271).
Clement of Alexandria - Strom. 4.23 On this wise it is possible for the [true] Gnostic already to have become God. “I said, Ye are gods, and sons of the highest.” (ANF 2.437).
Clement of Alexandria - Strom. 7.10 …they are called by the appellation of gods, being destined to sit on thrones with the other gods that have been first put in their places by the Saviour.(ANF 2.539).
Clement of Alexandria - Strom. 7.16 But he who has returned from this deception, on hearing the Scriptures, and turned his life to the truth, is, as it were, from being a man made a god.(ANF 2.551)
Tertullian - Adv. Hermogenes 5 Well, then, you say, we ourselves possess nothing of God. But indeed we do, and shall continue to do—only it is from Him that we receive it, and not from ourselves. For we shall be even gods, if we shall deserve to be among those of whom He declared, “I have said, Ye are gods,” and “God standeth in the congregation of the gods.” But this comes of His own grace, not from any property in us, because it is He alone who can make gods.(ANF 3.480).
Tertullian - Adv. Hermogenes 5 Well, then, you say, we ourselves at that rate possess nothing of God. But indeed we do, and shall continue to do—only it is from Him that we receive it, and not from ourselves. For we shall be even gods, if we shall deserve to be among those of whom He declared, “I have said, Ye are gods,” and “God standeth in the congregation of the gods.” But this comes of His own grace, not from any property in us, because it is He alone who can make gods. (ANF 3.480).
Some modern Catholic authors:
John Paul II - Jesus, Son and Savior This is the central truth of all Christian soteriology that finds an organic unity with the revealed reality of the God-Man. God became man so that man could truly participate in the life of God—so that, indeed, in a certain sense, he could become God. (P. 215 - Sept. 2, 1987 general audience address.)
Christoph Schonborn quotes from another Homily of John Chrysostom: “’God gave us a share in his throne. The sitting at the right hand is the greatest honor, with nothing to equal it. This statement holds true of us also: we too are to sit with him on thrones…. Think of where Christ sits on his throne! ‘Above all principalities and powers! And with whom are you to sit on the throne? With him!’” [in Schonborn, From Death to Life, op. cit., 39-40, quoting Homily on Ephesians 4.2. Once again, notice that the principalities and powers are subject to these deified mortals.]
And of course the text of the CCC 460:
“The only-begotten Son of God, wanting to make us sharers in his divinity, assumed our nature, so that he, made man, might make men gods.”
(which is a quote from Aquinas, and Schonborn was the editor of the CCC too).
The book Deification and Grace by Daniel Keating has many patristic and Biblical references to deification.
Hope that helps.
Charity, TOm