Isaiah 9:6-7 says: “For unto us a Child is born, Unto us a Son is given; and the government will be upon His shoulder. And His name will be called Wonderful, Counselor, Mighty God, Everlasting Father, Prince of Peace. Of the increase of His government and peace there will be no end, upon the throne of David and over His kingdom, to order it and establish it with judgment and justice from that time forward, even forever. The zeal of the Lord of hosts will perform this.”
Seemingly, the question presents a quandary – how can the Lord Jesus be both Father and Son? There are those who hold to a Unitarian point of view who would use this verse as an argument against the truth of the Trinity, that there is one God, existing in three Persons – Father, Son, and Holy Spirit. However, the Bible clearly teaches the Doctrine of the Trinity. Therefore, the verse cannot be suggesting that the Son is the Father.
There are two possible answers to the above. There are those who say the phrase should be translated “the Father of Eternity.” This is how J.N. Darby renders it in his translation as does F.C. Jennings, in his “Studies in Isaiah.” Rendered this way, the phrase is a figure of speech that refers to His relationship to time. The Septuagint omits the title altogether, but the marginal note gives the line from the Alexandrian Text as “the Father of the age to come.”
Being God, the Son has all the attributes of deity, equality with the Father (John 1:1-3). Having no beginning, He is eternal, existing outside of time. Furthermore, He is the One who governs time. This is confirmed in Hebrews 1:2 where it is said of Him that He has made the ages (YLT). Moreover, Isaiah 9:7 speaks of the future reign of Christ being the fulfillment of this truth that He governs the ages. Yet again, in Revelation 21:5 He is the One seated on the throne who says, “Behold I make all things new.”
The other view is that the phrase translated “Everlasting Father” (KJV, NKJV, and NIV) speaks of the Son’s tenderness and care. The care and concern that Israel lacked from its leaders according to Ezekiel 34, is supplied in the loving care of the Savior to His people. David in Psalm 68:5 refers to God as “a father to the fatherless” speaking of God’s care for His own. Meditating upon the Savior’s fatherly character (Cf. Mark 10:16), we can be comforted and rest securely in His eternal care for His people. We can cast our cares upon Him for we know He cares for us (1 Peter 5:7).
This thought is also expressed in Romans 8:37–39: “Yet in all these things we are more than conquerors through Him who loved us. For I am persuaded that neither death nor life, nor angels nor principalities nor powers, nor things present nor things to come, nor height nor depth, nor any other created thing, shall be able to separate us from the love of God which is in Christ Jesus our Lord.”
Attached to either view is the eternal existence of the Lord Jesus which He affirmed during His ministry on earth (John 8:58). As to His substance, He could say: “I and My Father are one” (John 10:30). He could also say to Philip: “He who has seen Me has seen the Father (John 14:9, e.g. Col. 1:15; Heb. 1:3).
In conclusion, Isaiah is expressing the greatness and future reign of the Messiah. He is the One who designed and created the ages and has a fatherly character demonstrated in His love and care for us.