Before we look at the word “gave” lets look at what God gave to the world. God gave what was “his”, so it belonged to Him. God can create anything and as many as He wants too. For God to give something to the world is no great sacrifice, except in this case where the gives His “only” begotten son. There is no other son like this one. He is unique and irreplaceable. This is a true sacrifice on God’s part.
This son is the only “begotten” son. That means God and the son are related by nature and not by adoption. It does not mean that God created the son, since both live in the realm of eternity. Neither of them have a beginning. This is simply talking about a relationship between the two.
The “son” is under the father’s authority by choice. The son placed himself under the authority of the father. They have the same nature of love and trust, and out of that love and trust the son placed himself under the father. The son is the perfect son of God and there is no one like him in all the universe. He is obedient to the father out of choice.
Now lets go back to the word “gave”. The only way for the world to receive the gift of Jesus Christ, the Son of God, was for God to give him to us. How can we ever pay for having Jesus? Is he worth all that we own? Sorry but we don’t own enough to purchase him even if we owned the whole world. Can we work hard and do enough good deeds? Your works are as filthy rags (Isaiah 64:6). We could work ourselves to death doing good deeds and never do enough.
To sell the son would be to say his worth is only so much. It would be insulting to put a price tag on the life of God’s only begotten son. If God wanted to save the world He had to give the greatest gift that He possibly could give. Out of His love for the world, God sacrificed what only He could give. God so loved the world that he gave his only begotten son.