The First Christians Worshiped Jesus

Sacrifice 

Revelation 14:4 New Revised Standard Version 4 It is these who have not defiled themselves with women, for they are virgins; these follow the Lamb wherever he goes. They have been redeemed from humankind as first fruits for God and the Lamb,

Revelation 20:6 New Revised Standard Version

6 Blessed and holy are those who share in the first resurrection. Over these the second death has no power, but they will be priests of God and of Christ, and they will reign with him a thousand years.

1.The Old Testament shows that no one else received sacrifice except Yahweh. That differentiates Yahweh from any other being.

2. Sacrifice is a very strong evidence for "worship" at the highest order. And in other heathen religions, sacrifice is only offered to a god by priests. So, in the ancient world, priests always always offer sacrifice to a god(s)/God, never to any human.

3. Christians are offering sacrifices to both God and Christ. In Revelation 14:4 , 20:6 this is explicit.

4. Revelation 14:4, 20:6, priests offer sacrifices to both God and Jesus. Sacrifice in the Old Testament is exclusively offered to a god, never to a man. Israel obviously offers sacrifices to Yahweh alone. Thus, here in Revelation 14:4, 20:6, Jesus is shown to be the Lord God.

1 Chronicles 29:20 says that the people worship YHWH and the king (προσεκύνησαν Κυρίῳ καὶ τῷ βασιλεῖ). YHWH is not literally present in the area. The Israelite king was sitting on his throne and there was no visible YHWH besides him. Revelation is explicit as to what worship is given, it's given by priests. That's offering/sacrifice given to two figures present at the scene: Father and Jesus jointly. Also, Revelation 14:4 had them offering first fruits to the Father and the Lamb, that is again sacrifice offered to them both as a unit. And they were all both equally present at the scene. How are all these compare to 1 Chronicles 20:6?

In Revelation 20:6, priests are serving God and Christ. Priests always serve only deities (never humans) in the Old Testament. Revelation 20:6 is explicit that Christ is not only human but also God together with the God he is with, the Father. In the text, the priests serve them both as a unit, as a single recipient of worship based on grammar. Jesus is the Lord, the God of the spirits of the prophets and also the Almighty, as indicated also in Revelation. It is not 2 Gods being worshiped in the text but 1 God (the Father) and 1 Lord (Christ), the pattern followed by the earliest churches as recorded in Paul's letters where the Father and Jesus were both equated to the 1 Lord God of the Jewish Prayer Shema Yisrael (For us there is one God, the Father....and one Lord, Jesus Christ, 1 Corinthians 8:6, Lord our God, Lord is one, Deuteronomy 6:4).

Revelation 20:6

William Henry Simcox: τοῦ θεοῦ καὶ τοῦ Χριστοῦ. The strongest proof, perhaps, in the book of the doctrine of Christ’s coequal Deity. (The Revelation of St. John the Divine, Cambridge Greek Testament for Schools and Colleges) source: http://www.studylight.org/commentaries/cgt/revelation-20.html

Romans 16:5

Romans 16:5 

Likewise greet the church that is in their house. Salute my well-beloved Epaenetus, who is the firstfruits of Achaia unto Christ. 

Albert Barnes: Who is the first-fruits - One who first embraced Christianity under my preaching in Achaia. The “first-fruits” were a small part of the harvest, which was first gathered and offered to the Lord; Exodus 22:29; Exodus 23:16; Leviticus 2:12; Deuteronomy 18:4. In allusion to this, Paul calls Epenetus the first-fruits of the great spiritual harvest which had been gathered in Achaia. source: https://www.studylight.org/commentaries/eng/bnb/romans-16.html

The earliest Christians presented their bodies as a living sacrifice, holy and acceptable to God and to Christ which was their spiritual worship: 

Romans 12:1 New Revised Standard Version

12 I appeal to you therefore, brothers and sisters,[a] by the mercies of God, to present your bodies as a living sacrifice, holy and acceptable to God, which is your spiritual worship.

2 Corinthians 5:9-10 New Revised Standard Version

9 So whether we are at home or away, we make it our aim to please him. 10 For all of us must appear before the judgment seat of Christ, so that each may receive recompense for what has been done in the body, whether good or evil.....15 And he died for all, so that those who live might live no longer for themselves, but for him who died and was raised for them.

The same Greek word for acceptable in Romans 12:1 is used for pleasing in 2 Corinthians 5:9 in reference to the Lord Jesus. 

1 Corinthians 6:13 New Revised Standard Version

13 “Food is meant for the stomach and the stomach for food,” and God will destroy both one and the other. The body is meant not for fornication but for the Lord, and the Lord for the body.

1 Corinthians 7:32, 7:34 New Revised Standard Version

32 I want you to be free from anxieties. The unmarried man is anxious about the affairs of the Lord, how to please the Lord; 34 and his interests are divided. And the unmarried woman and the virgin are anxious about the affairs of the Lord, so that they may be holy in body and spirit; but the married woman is anxious about the affairs of the world, how to please her husband. 

Philippians 1:20 New Revised Standard Version

20 It is my eager expectation and hope that I will not be put to shame in any way, but that by my speaking with all boldness, Christ will be exalted now as always in my body, whether by life or by death.

Ephesians 5:10 New Revised Standard Version

10 Try to find out what is pleasing to the Lord. 

Romans 14:7-8 New Revised Standard Version

7 We do not live to ourselves, and we do not die to ourselves. 8 If we live, we live to the Lord, and if we die, we die to the Lord; so then, whether we live or whether we die, we are the Lord’s.

On Romans 14:7-8 

1. Murray Harris: Nowhere in the New Testament is the absoluteness of the Lord's ownership of his douloi depicted more clearly than in Romans 14:7-8 (Slave of Christ: A New Testament Metaphor for Total Devotion to Christ, page 112).

2. Charles Hodge: It is very obvious, especially from the following verse, which speaks of death and resurrection, that Christ is intended in the word Lord, in this verse. It is for Christ, and in subjection to his will, that every Christian endeavors to regulate his heart, his conscience, and his life. This is the profoundest homage the creature can render to his Creator; and as it is the service which the Scriptures require us to render to the Redeemer, it of necessity supposes that Christ is God. source: http://www.studylight.org/commentaries/hdg/romans-14.html#1

Prayer

Acts 7:2, 7:30-33, 7:59-60 (NRSV)
Then the high priest asked him, “Are these things so?” 2 And Stephen replied:
“Brothersand fathers, listen to me. The God of glory appeared to our ancestor Abraham when he was in Mesopotamia, before he lived in Haran, 30 “Now when forty years had passed, an angel appeared to him in the wilderness of Mount Sinai, in the flame of a burning bush. 31 When Moses saw it, he was amazed at the sight; and as he approached to look, there came the voice of the Lord: 32 ‘I am the God of your ancestors, the God of Abraham, Isaac, and Jacob.’ Moses began to tremble and did not dare to look. 33 Then the Lord said to him, ‘Take off the sandals from your feet, for the place where you are standing is holy ground....59 While they were stoning Stephen, he prayed, “Lord Jesus, receive my spirit.” 60 Then he knelt down and cried out in a loud voice, “Lord, do not hold this sin against them.” When he had said this, he died.

The dying Stephen's prayer to Jesus alludes to the dying Jesus' own prayer to the Father in the gospels. This shows Stephen regarded Jesus as the OT Lord God. Also, in the same chapter, Stephen spoke of the same Lord as the God of Glory who appeared to Abraham. In 1 Corinthians 2:8, Jesus is the crucified Lord of Glory, the same Lord spoken of in Joel 2:32 whose name everyone calls on in the same letter in 1 Corinthians 1:2. In Acts 7:3, Jesus is the God of Glory who appeared to Abraham, Jesus is that Lord God in Joel 2:32 whose name everyone calls on in the same book in Acts 2:21, Acts 2:38, and Acts 22:16. Romans 10:12 has Jesus as Lord of all and Acts 10:36 also has Jesus as Lord of all. Both Paul's letters and the book of Acts apply the same text , an OT YHWH text, Joel 2:32 (3:5 LXX) to Jesus, identifying him as the one Lord God of the OT.

Note

1. An angel-appearance or man-appearance isn't a theophany if the angel or man that appears isn't God. When the God of Glory appeared (Hebrews 7:3) ---as an angel who was identifed as the Lord (Hebrews 7:30-33) and who was specifically identified as the Lord Jesus in the same chapter (7:58-59) ---he really did appear to Abraham and conversed with him (cf. John 8:56-58).

John 14:14
14 "If you ask Me anything in My name, I will do it.

Acts 1:24-26
And they prayed and said, "You, Lord, who know the hearts of all men, show which one of these two You have chosen 25to occupy this ministry and apostleship from which Judas turned aside to go to his own place." 26And they drew lots for them, and the lot fell to Matthias; and he was added to the eleven apostles

Acts 8:22
"Therefore repent of this wickedness of yours, and pray the Lord that, if possible, the intention of your heart may be forgiven you

1 Corinthians 1:1-2

Paul, called to be an apostle of Christ Jesus by the will of God, and our brother Sosthenes,

2 To the church of God in Corinth, to those sanctified in Christ Jesus and called to be his holy people, together with all those everywhere who call on the name of our Lord Jesus Christ—their Lord and ours:

2 Cor 12:8-10
8 Concerning this I implored the Lord three times that it might leave me. 9And He has said to me, "My grace is sufficient for you, for power is perfected in weakness." Most gladly, therefore, I will rather boast about my weaknesses, so that the power of Christ may dwell in me. 10Therefore I am well content with weaknesses, with insults, with distresses, with persecutions, with difficulties, for Christ's sake; for when I am weak, then I am strong.

James 1:1-8
James, a bond-servant of God and of the Lord Jesus Christ,
To the twelve tribes who are dispersed abroad: Greetings.
2 Consider it all joy, my brethren, when you encounter various trials, 3knowing that the testing of your faith produces endurance. 4And let endurance have its perfect result, so that you may be perfect and complete, lacking in nothing.
5 But if any of you lacks wisdom, let him ask of God, who gives to all generously and without reproach, and it will be given to him. 6But he must ask in faith without any doubting, for the one who doubts is like the surf of the sea, driven and tossed by the wind. 7For that man ought not to expect that he will receive anything from the Lord,8being a double-minded man, unstable in all his ways.

1 John 5:14-15
14 This is the confidence which we have before Him, that, if we ask anything according to His will, He hears us. 15And if we know that He hears us in whatever we ask, we know that we have the requests which we have asked from Him.

Singing together hymns, psalms and a new song

Singing together hymns, psalms to the Lord (Ephesians 5:19, Colossians 3:16). In the Bible, singing together hymns, psalms to the Lord is called ''offering sacrifice of praise to the Lord'' (Hebrews 13:15). ''For us there is one Lord, Jesus Christ (1 Corinthians 8:6). In Revelation 5:9 and 14:3, everyone sings a ''new song'' to both God and the Lamb (the Lord Jesus). In the book of Psalms, people only sang a ''new song'' to God (Psalm 40:3, 96:1).  

The Greek word ''proskuneo'' is usually translated into English as ''worship'' (etymologically means ''acknowledging of worth''). This meaning of worship is indeed in the Bible. To worship God means to acknowledge his worth because of what he has done. In Revelation 4:11, everyone is acknowleding that God is worthy to receive glory, honor and power because he created all things. In Revelation 5:9, everyone is acknowledging that the Lamb (Jesus) is worthy to take the scroll and to open its seals, because he was slain and by his blood he ransomed people for God etc. They were singing this as a ''new song'' to Jesus. In Revelation 5:13, every creature is giving ''blessing and honor and glory and might forever and ever'' to both God and the Lamb. Jesus' death on a cross is the reason why he's being worshiped but the worship he receives the same kind of religious worship God himself receives. This deviates from the Old Testament worship practises. Honoring God through singing psalms and a new song to him in the Old Testament is normal and expected but honoring God and the human Jesus through singing psalms and a new song to them is something unprecendent in the judaisms of the ancient world. 

The 24 elders specifically worshiped Jesus the way the Lord God is worshiped i.e. via a new song and offering of incense (prayers). Only YHWH is worshiped through a new song and incense (prayers) in the OT.

Revelation 5:9-10

8 And when he had taken the scroll, the four living creatures and the twenty-four elders fell down before the Lamb, each holding a harp, and golden bowls full of incense, which are the prayers of the saints. 9 And they sang a new song, 

Psalm 96:1
New Revised Standard Version

Praise to God Who Comes in Judgment
1 O sing to the Lord a new song;
sing to the Lord, all the earth.

Note

1. In Revelation 5, the reasons for worshiping them are different but the kind of worship given to both God and the Lamb are the same ("blessing, honour, glory and power for ever") plus it is described as a "new song" which is what exactly the psalms are addressing Yahweh in the OT.

Answering a Unitarian who insist that Jesus was not worshiped as God in Revelation 5: 

You insist that because the reasons differ, the worship also must differ but the biblical text indicates that while the reasons differ, the worship offered is identical in Revelation 5.

Every knee bends

"every knee bends to me'' ( i.e. to the Lord God", based on context of Isaiah 45:23 LXX) every knee bends in the name of Jesus and every tongue confesses Jesus is Lord to God the Father's glory" Philippians 2:10-11). Paul applies the OT "YHWH text" to Jesus and the Father in Philippians 2:10-11, equating Jesus and the Father to the 1 Lord God of Isaiah 45.

Note

1. The Greek word usually translated into English as ''worship'' is ''proskuneo'' which means ''to kneel down [before someone]''. The phrase ''every knee shall bow'' (''every knee should bend'', NRSV, ) is found in Isaiah 45:23 in the Septuagint (καμψει παν γονυ - ''kamse pan gony'') and in Philippians 2:10 in the Greek New Testament ( πᾶν γόνυ κάμψῃ - ''pan gony kamse''). This phrase is the very definition of ''proskueno''. People do proskuneo to kings, angels, God etc. It's not exclusive to God. In Philippians 2:10-11, all created things worship Jesus as Lord and the Father as God, affirming that Jesus as Lord and the Father as God are both uncreated since all created things worship them both. 

2. Paul believed that Jesus had a prehuman existence both ''in the form of God'' and as ''equal with God'' (as Lord) prior to becoming in the likeness of men/found in the form as a man (Philippians 2:6-7). Paul believed that Jesus, as Lord, was Creator [of all created things] together with the Father in 1 Corinthians 8:6.