“Come near to Me, hear this: I have not spoken in secret from the beginning; from the time that it was, I was there. And now the Lord God and His Spirit have sent Me” (Isaiah 48.16).

The Lord Jesus is the Servant being sent in this passage. The Father is called the Lord God. The Holy Spirit and the Father send the Son. This is a clear reference to the triunity of God. The Father sent the Son to save all the ends of the earth from sin and Hell. The Holy Spirit not only sent the Lord Jesus, but He illumined the path ahead of Him. He revealed the way of salvation through the Son. The Trinity is not an obscure teaching in the Old Testament. 

God the Father is the speaker in Genesis 1.26. He said, “Let us make man in Our image, according to our likeness.” The pronouns indicate a plurality of persons involved in the creation of man. This occurs again when man is punished for his rebellion and sin: “Then the LORD God said, “Behold, the man has become like one of Us, to know good and evil” (Genesis 3.22). Notice again the plural pronoun. When God confused the languages because of mankind’s unified effort against Him in building the Tower of Babel, we read: “Come, let Us go down there and confuse their language” (Genesis 11.7). 

Isaiah 11.2 states that the Spirit of the LORD (the Father) shall rest upon Him (the Son). This occurs again in Isaiah 61.1: “The Spirit of the Lord God (the Father) is upon Me (the Son), because the LORD (the Father) has anointed Me to preach good tidings to the poor.” Zechariah 2.11 states, “Many nations shall be joined to the LORD (the Father) in that day, and they shall become My (the Son’s) people. And I will dwell in your midst. Then you will know that the LORD of hosts has sent Me to you.”