---On the Christian doctrine of the Trinity
Christmas is becoming more and more secular and commercial, with the Santa Claus---a cheerful old man with red and white fur, a long white beard, and with a black belt at his waist--- as the main symbol.
Santa Claus is from Saint Nicholas (AD. 270-343) who was born in Lucia (now in Turkey) in Asia Minor. He was the bishop of the city of Mira in the third and fourth centuries. He was persecuted during the reign of the Roman Emperor Diocletian, and was later released during the reign of Diocletian’s successor Constantine and was invited to participate in the First Council of Nicaea in AD 325. （第一次尼西亚大公会议）
There are two anecdotes about St. Nicholas that are widely circulated. First, he often quietly gave gifts to those in need, this is why he became the prototype of later Santa Claus. Second, he Adhered to the truth without compromise. At the first Council of Nicaea, he was very angry with the heresy of Arianism (which denies the deity of Christ), he was so angry that he even slammed a punch on the face of Arius. （St. Nicholas couldn’t imagine that his name was abused as Santa Claus. If he is still alive today, according to his uncompromising personality, he will again punch the face of Santa Claus. ）
In Nicene creed（尼西亚信经）, a special term Homoousios was adopted to describe Jesus Christ as “same in being, same in essence” with God the Father (ὁμοούσιον τῷ Πατρί).（ “The same term was later also applied to the Holy Spirit in order to designate him as being "same in essence" with the Father and the Son.”）(Wikipedia, under the term of Homoousion)
There is a similar term Homoiusios, which means “similar in being or essence.” It denied that Jesus Christ has the same nature with God the Father, but only a similar nature with God.
In a Cartoon picture, a boy asked the Santa Claus, “Homoousios or Homoiusios?” The Santa Claus was greatly puzzled, “What?” Then the boy said to him, “Hmm, you are not the real St. Nicholas.”
“In the beginning was the Word, and the Word was with God, and the Word was God. He was with God in the beginning. Through Him all things were made; without Him nothing was made that has been made.” （“太初有道，道与神同在，道就是神。这道太初与神同在。万物是借着祂造的。凡被造的，没有一样不是借着祂造的。”）（约/John 1:1-3）
Last Sunday’s sermon was entitled with “In the beginning was the Word,” this passage indicates not only its strong apologetic feature of the gospel of John, it also demonstrates its profound theological significance of this book.
“In the beginning was the Word, and the Word was with God, and the Word was God.” （“太初有道，道与神同在，道就是神。”）(约/John 1:1)
“The Word was with God.” Obviously, the Word was distinct from God, yet He was God. Meanwhile, the Word was actively engaged in the creation of the world, for “Through Him all things were made.”（“万物是借着祂造的。”） (约/John 1:3)
Now the problem arises: How can God be with God?
This great question leads to a great Christian doctrine---Trinity, which was originated from the First Council of Nicaea.
The term “Trinity” (or Triunity) is the most famous and mysterious term in Christian doctrine, it has never appeared in the Bible.
Then you may ask: is it biblical? Surely it is! As a matter of fact, it is a fundamental doctrine for Christian faith. Whether accept or deny this doctrine, is the distinguishing mark between the authentic Christianity and all kinds of heresy.
Many people have attempted to invent some analogies to explain or better understand the term Trinity, such as water with its three states: the solid ice, the liquid water and the gas vapor; the Sun and its three features: Light, Heat and energy. Yet none of them is correct, they may sound similar, but they are totally different from the truth of Trinity. Therefor no one can truly understand or explain this concept.
“The secret things belong to the LORD our God.”（“隐秘的事是属耶和华我们神的。”）（申/Deut 29:29）
Trinity the definition:
“God eternally exists as three Persons, Father, Son and Holy Spirit, and each Person is fully God, and there is one God.” (Wayne Grudem)
“There is one only and true God, but in the unity of the Godhead there are three coeternal and coequal Persons, the same in substance but distinct in subsistence.” (B. B. Warfield)
I. The concept in the Old Testament（旧约的启示）
A. The Unity of God（神的独一属性）
“Hear, O Israel: The LORD our God, the LORD is one. Love the LORD your God with all your heart and with all your soul and with all your strength. These commandments that I give you today are to be on your hearts. Impress them on your children. Talk about them when you sit at home and when you walk along the road, when you lie down and when you get up. Tie them as symbols on your hands and bind them on your foreheads. Write them on the doorframes of your houses and on your gates.” (Deut 6:4-9)
“Hear, O Israel: The LORD our God, the LORD is one.” （以色列啊，你要听。耶和华我们神是独一的主。） (申/Deut 6:4)
“Remember the former things, those of long ago; I am God, and there is no other; I am God, and there is none like me.” （“你们要追念上古的事，因为我是神，并无别神，我是神，再没有能比我的。”）(赛/Isa 46:9)
B. The plural form expressions（神的复数表达形式）
“Then God said, "Let us make man in our image, in our likeness.” （“神说，‘我们要照着我们的形像，按着我们的样式造人。’”）(创/Gen 1:26)
“(The LORD said), Come, let us go down and confuse their language so they will not understand each other." （“【耶和华说，】‘ 我们下去，在那里变乱他们的口音，使他们的言语彼此不通。’”）(创/Gen 11:7)
“Then I heard the voice of the Lord saying, ‘Whom shall I send? And who will go for us?’" （“我又听见主的声音，说，‘我可以差遣谁呢？谁肯为我们去呢？’”）(赛/Isa 6:8)
“Your throne, O God, will last for ever and ever; a scepter of justice will be the scepter of your kingdom. You love righteousness and hate wickedness; therefore God, your God, has set you above your companions by anointing you with the oil of joy.” (Ps 45:6-7)
The author did not talk to any human king, but to “God” whose throne will endure forever and ever, He said, “Your God, has set you above your companions,” obviously there are two persons are to be called “God.” (in the New Testament, the author of Hebrews applied Him to be Jesus Christ.)
“But about the Son He says, "Your throne, O God, will last for ever and ever, and righteousness will be the scepter of your kingdom. You have loved righteousness and hated wickedness; therefore God, your God, has set you above your companions by anointing you with the oil of joy."(Heb 1:8-9)
These two passages are almost identical only the Heb 1:8 adds the phrase: “But about the Son He says.”
“The LORD says to my Lord: ‘Sit at my right hand until I make your enemies a footstool for your feet.’"（“耶和华对我主说，‘你坐在我的右边，等我使你仇敌作你的脚凳。’”）（诗/Ps 110:1）
There are two Lords here, and who can sit at the right hand of God but God Himself?
“Then the LORD rained down burning sulfur on Sodom and Gomorrah--from the LORD out of the heavens.”（“当时，耶和华将硫磺与火从天上耶和华那里降与所多玛和蛾摩拉。”） (创/Gen 19:24)
Again, there are two LORDs here, one is in heaven, and one is on earth.
“‘The Redeemer will come to Zion, to those in Jacob who repent of their sins,’ declares the LORD. ‘As for me, this is my covenant with them,’ says the LORD. ‘My Spirit, who is on you, and my words that I have put in your mouth will not depart from your mouth.’” (Isa 59:20-21)
Notice that the Lord, the Redeemer, the Spirit of the Lord, all three appeared here in this passage.
“The Spirit of the Sovereign LORD is on Me.” （ “主耶和华的灵在我身上。” ）(赛/Isa 61:1)
“And now the Sovereign LORD has sent Me, with His Spirit.” （“现在主耶和华差遣我和祂的灵来。”）(赛/Isa 48:16)
Note that three persons appeared in these verses: the LORD, the Spirit of the LORD, and Me.
C. The Angel of the Lord（耶和华的使者）