Christ as the Only Begotten Son

Brothers and sisters, as we examine Lord’s Day 13 and Question 33 of the Heidelberg Catechism, we ask, “Why is Christ called the only begotten Son of God?” This question directs us to consider why Jesus is uniquely identified as the eternal and natural Son of God.

The Two Types of Sons: Natural and Adopted

There are two types of sons:

1. Natural sons, who belong to their parents by nature from the moment they exist.
2. Adopted sons, who already exist but are brought into a family later by choice.

Christ is uniquely the natural Son of God according to His divine nature. He is of the same essence and nature as the Father, begotten from everlasting. This is a profound mystery, incomprehensible to us as finite creatures.

As John 5:26 says, “As the Father has life in Himself, so He has granted the Son to have life in Himself.” This reveals Christ’s eternal divine Sonship, distinct from His human nature.

The Sonship of Christ in His Humanity

According to His humanity, Christ is not the natural Son of God but is called the Son of God by:

1. Grace: Not the grace of adoption, but the grace of conception by the Holy Spirit.
2. Union with the Word: In His humanity, Christ was not begotten from the Father’s essence, but He became the Son of God from the moment He began to exist.

Unlike Christ, there was a time when we existed but were not children of God. Before our adoption, we were His enemies, hostile to Him. Through faith in Christ, we become children of God—not by natural birth or conception, but by the grace of adoption.

Adoption as Sons of God

Ephesians 1:5–6 explains this adoption:
“He predestined us for adoption to Himself as sons through Jesus Christ, according to the purpose of His will, to the praise of His glorious grace.”

This is why Christ can be the only begotten Son and yet have brothers. Christ’s sonship is by eternal generation and divine nature, while our sonship is by the grace of adoption. We share the same Father as Christ through this grace, though His Sonship remains incomparably superior.

Four Aspects of Our Brotherhood with Christ

Zacharias Ursinus identifies four ways we are Christ’s brothers:

1. Human Nature: Christ took on our human nature, making us of like kind. We are not brothers to animals, but to those who share human nature.
2. Brotherly Love: Christ shows us perfect brotherly love.
3. Conformity with Christ: God shapes us to bear the same character as Christ, the perfect God-man. As Jesus said in John 14:9, “Whoever has seen Me has seen the Father.”
4. Participation in Christ’s Benefits: All God’s children share in the blessings Christ secured.

The Superiority of Christ Over His Brothers

Though we are brothers with Christ, He is infinitely superior:

• According to His Deity: Christ is the eternal, begotten Son of God, equal to the Father in essence and nature.
• As Creator and Redeemer: Hebrews 1:8 declares, “Your throne, O God, is forever and ever.”

Christ existed as the only begotten Son before being sent into the world. He is not a lesser deity but fully God, deserving equal praise with the Father.

The Humility and Sacrifice of Christ

Philippians 2:6–7 reminds us of Christ’s humility:
“Though He was in the form of God, He did not count equality with God a thing to be grasped, but emptied Himself, taking the form of a servant.”

Christ became man, suffered, and died so that we might become children of God. Through His work, we share His Father, and though adopted, we are treated with the same love as natural-born sons.

Adapted from the sermon “The Only Begotten Son, Our Lord” Heidelberg Catechism, Lord’s Day 13, Questions 33 & 34.