(I finally managed to gather up my notes from the CCA this past summer, and to put them in some semblance of order. With apologies for any lack of clarity or coherence, here they are.)
The Fatherhood of God is not simply an attribute of God, nor only a metaphor, nor even first of all an action or attitude of God, but His Fatherhood belongs to the essential identity of who and what God is; so also the Sonship of God. For the one true God is the Father from all eternity, as one and the same true God is the Son from all eternity. The relation of the Father and the Son within the Godhead, in the love of the Holy Spirit, comprises both the distinction and the unity and harmony of the three Persons of the Holy Trinity.
The Father is the Father of the Son, and the Son is the Son of the Father, and the Holy Spirit is the Spirit of the Father and the Son, and this intra-Trinitarian relationship is the essential and eternal being of God. It is the “necessity” of His divine being, of who and what He is, and so also the fountain and source of His perfect freedom. God does not become a father because He creates and gives life, but He creates and gives life because He is the Father.
He is the God and Father of our Lord Jesus Christ, the incarnate Son, and it is from and with and in that Fatherhood of God that He freely and graciously chooses to become our Father in Christ. For no one knows the Father except the Son and anyone to whom the Son chooses to reveal Him. No one comes to the Father but by Him.
He who is true God, begotten of the Father from eternity, has also become true Man, our brother in the flesh, conceived and born of the Blessed Virgin Mary, that we might be “conceived” and “born again” by His Word and thereby receive the adoption of sons by His grace. What Christ is by nature, from all eternity, we become by such gracious adoption, unto the life everlasting.
We receive the adoption of sons, so that God becomes our Father, and so that Christ the beloved Son become the firstborn of many brethren. Our adoption is therefore rooted in Christ, both in His eternal Sonship and in His Incarnation by the Blessed Virgin Mary. His Sonship becomes ours by His grace through the Gospel, through the catechesis of His Word, by the preaching of repentance for the forgiveness of our sins in His Name, and by our Baptism into His Cross and Resurrection. Such is our new birth of water, Word and Spirit.
So do we pray, as Christ has taught us and invited us to pray, “Our Father who art in heaven,” and so do we cry out to Him in faith, “Abba! Father!”
These gracious good gifts of God are the fulfillment of His creation of man in His own Image and Likeness, even as we are recreated and made brand new, conformed to the Image of His Son by the way of the Lord’s Incarnation, Cross and Resurrection for us.
Earthly fatherhood is likewise rooted in that divine work of creation by our Father in heaven, as being a husband is rooted in the divine work of redemption by our heavenly Bridegroom, Christ Jesus. The fact that man is made in the Image of God, both male and female, the woman for the man, and the wife given to her husband to be united to him as one flesh, reflects the loving unity of the three Persons within the one Godhead. It is the Father’s love for the Son, and the Son’s love for the Father, which moves God in His perfect freedom to create man and call Him to Himself, to be His holy Bride, the Church.
As husbands and wives are fruitful and multiply by the gracious Word and work of God, so do Christ and His Church give birth to the children of God by His Word and Holy Spirit. It is for these reasons that a man leaves his father and mother to be joined to his wife and cleave to her in love, and for these reasons that fathers give their daughters in marriage. Accordingly, the first and foremost thing that fathers are given to do for their children, is to love and serve and care for their wives.
So marriage and family are rooted in the gracious freedom and love of husbands and fathers, who receive their calling from the God and Father of our Lord Jesus Christ. This grace of God, in turn, is the inheritance that husbands share with their wives and fathers bestow upon their children.
Thus does Christ, the eternal Son, become the “everlasting Father,” not in His divine personhood in relation to God the Father, but in His redemption and reconciliation of the Church to God. As the Image of the Father, He is also like His Father in begetting children by His Bride, the Church. He cares for them and provides for them, serves them and protects them, teaches them and feeds them, gives them His name and bestows all His gifts and benefits upon them. For He is the new and greater Adam, the Head of a new humanity, and He is the One in whom all the promises of God to Father Abraham are realized, as a blessing to all nations, to all who are the children of Abraham by faith.
In Christ, therefore, is found the freedom and responsibility of fatherhood — in contrast to the different character and quality of motherhood. Mothers become such by receiving what is given to them, but fathers are such by the choice of love; not the "choice" of conception of new life, which remains the prerogative and work of God, but the willing choice and commitment to love and care for those children who are thus conceived. In that respect, every father chooses to “adopt” his children, whether they are his biologically or not, as St. Joseph chose to adopt the Son of Mary, who is the very Son of God.
In fact, there are many different kinds and types of earthly “fatherhood,” both large and small, which are granted in various ways by the vocation of God through His Word, and which are governed by His Word.
“Call no man father,” Jesus says, “for One is your Father, even God.” But He does not thereby prohibit a man from being called a father, for it is by God the Father that every fatherhood on earth is called and named.
Thus do Christian men adopt and care for widows and orphans in their distress, and in this way they exemplify, express and extend the Fatherhood of God on earth as it is in heaven, especially in and through and with His Church. Men receive this calling from God, and they take it up in faith and love, by His Word and Holy Spirit in Christ Jesus.
What it means, therefore, to be a man, is to be a husband and a father after God’s own heart — whether in relation to one’s own earthly wife and biological children, or by way of adoption, or by caring for widows and orphans in their distress, or by caring for the Lord’s Church, the Bride of Christ and the Mother of God’s children, by the spiritual fatherhood of the pastoral office. What it means to be a man is found in Christ Jesus, the Son of God, who is the perfect Image of the Father. What it means to be a man is defined and determined by His Word.
Fathers, name your children, then, as God the Father names you in Christ with His own name.
Love your wives, and love the Bride of Christ, and love the children entrusted to your care with the love that Christ has for you and for His Church. In such love, give and nurture life, guard and protect it. Feed and teach your children. Prepare them for marriage, or help them to discern the divine gift and calling of celibacy in service to the household and family of God. Teach your sons how to become men after God’s own heart, to become husbands and fathers like Christ. And likewise teach your daughters, by word and example, what a good and faithful man is like, and show them how a man is to care for a woman with gentle integrity and the strength of mercy and peace.
Catechize your children; pray and confess the Word of Christ with them. Lead them and guide them, again, by your words and by your own godly example. Discipline them in love, that they might learn the life of love. Do so with mercy, compassion, forgiveness and self-sacrifice, that they might learn to live by faith in the Gospel. Demonstrate the humility of repentance and the confidence of faith.
In all of this, the grace and strength of human fatherhood is the Fatherhood of God in Christ Jesus. He calls you and names you, sustains you and upholds you, by His own Fatherhood, which is steadfast and eternal in the relationship of the Father and the Son in the Holy Spirit.