Eternal generation
The Son must be eternally Generated
Eternal generation
The Son is eternally generated/begotten.
First I want to explain what generation is. As trinitarians we believe the Father, Son and Spirit share the same divine nature, will attributes, and so on. There are distinctions between the persons, and the persons are not distinct in what they are but their manner of existence (tropos). The distinctions are filiation from the Father, generation from the Son, and spiration from the Spirit. Each of these distinctions are the relations they have between each other, but these distinctions do not start at a point they have eternally been distinct in this way. Generation is the distinction of the person of the Son that is eternally unchanging.
About the Son, the Son must be eternally generated or begotten. There wasn’t a moment where he wasn’t. Many argue that the Son isn’t eternal or isn’t eternally generated/begotten. I want to show through the scriptures and the use of logic this is necessary.
This is important because it hinges on how salvation acts to us. If you don’t believe in this view there are a few views you fall into and all are problematic.
1. Some believe that the Son only came to existence at the womb of the Virgin Mary. This ends up being a form of Adoptionism. If he becomes a son then he gets a title he previously didn’t have, which is a form of Adoptionism. If he becomes adopted then he is not the original Son, and there is no distinction between us and him. He becomes just as adopted as us, meaning he cannot actually give us something eternally because he does not have it. He ends up being the recipient of sonship thus he cannot give. There is nothing special about Jesus. This leads to Jesus just being a mere creature, and how could a creature bridge the gap between man and God? We can also take it the other way, if you do believe Jesus is God, but wasn’t eternally generated. If that’s what you believe, then you have multiple ungenerated persons in the Trinity which causes no distinction at all between them in eternity past.
2. This also leads to Arianism, because the historical Arian position is “there was a time the son was not”. if the Son did not always exist, then logically there must also have been a time when the Father was not the Father. For if there were no Son, then in what sense could God be the Father before creation? The concept of a father presupposes a son. Another problem is if the Son has not always been the Son, then something has changed in the Father: the Father has gone from not being Father to being Father. But if there is a real change in God, this compromises the immutability of God. Of God can change in his essence and eternal relations, then there poses a problem concerning if he’s trustworthy. If God promises salvation what basis do you have that you know that salvation won’t change.
3. Another view is subordinationism. Which was already condemned but seems to be very problematic. If you affirm subordinationism then you are saying the Son submits to the Father. Which this makes the claim that since the person of Son must submit to the Person of the Father then that makes two wills within the Trinity. If you have two wills along with two unoriginated persons you collapse into polytheism.
4. I think our biggest argument biblically for the eternal generation of the Son is John 1:18. This passage explicitly says the Son is in the bosom of the Father, or the Fathers side, this is explicitly important. The bosom of the Father meant a really close intimate relationship sort of like at a table with someone. In John 1:18 there is a Greek word ό όν (ho on) “on” is a present participle after a definite article which changes the meaning that the Son doesn’t have a beginning. The term (ho on) makes the meaning literally “the one who is continuously in the bosom of the father”. Because the present participle is for the noun. When the present participle is used with a definite article it turns the verb into a substantival participle. In layman’s it’s sorta like a perminant state that’s just who or where he is that’s almost like it’s identity. So when you apply it to Christs relationship with the father he is eternally in that state of being a Son because that is his identity. We have other passages such as in the Greek Septuagint like Psalm 110:3 and many others that the Fathers used in Nicaea and that are pretty clear about Jesus. This is very important because if Christ had to become a Son or isn’t eternal he cannot give us things he doesn’t have. I pray this helps someone.
If you do not have an eternal Generated Son then you don’t have an eternal Father or a way to be adopted into sonship permanently. Seek the Son through the scriptures.