Given the nature of my last post, I figured that it would be helpful to post the textual data from Col 1:15 for you to take a look at. Notice specifically the words “image” and “firstborn” in this verse, and how they testify to the absolute deity of YHWH the Son.
1:15 who is (the) imagea of-the invisible/unknownb God, (the) firstbornc of-all creation,d
LEXICON—a. εἰκών (LN 58.35; 58.61) (BAGD 1.b. p. 222): ‘image’ [BAGD, Herm, Lns, NIC, NTC, WBC; KJV, NAB, NASB, NIV, NJB, NRSV, REB], ‘likeness’ [BAGD, LN (58.35)], ‘representation’ [LN (58.61)], ‘visible likeness’ [TEV], ‘visible image’ [NLT]. The clause ὃς ἐστιν εἰκὼν τοῦ θεοῦ ‘who is the image of God’ is translated ‘He in his own person shows us what God is like’ [TNT], ‘is exactly like God’ [CEV], ‘he reveals perfectly what God is like’ [SSA]. This word includes a likeness, a representation and a revealing [EG, Lt, SSA], a likeness in an essential characteristic or attribute [ICC], a visible [Ea, EG, My], exact and perfect representation in every detail [Ea]. The word itself does not indicate perfect resemblance [ICC, Lt], nor does it necessarily indicate visibility [Lg]. See this word at 3:10.
b. ἀόρατος (LN 24.4) (BAGD p. 79): ‘invisible’ [BAGD, Herm, LN, Lns, NIC, NTC, WBC; all versions except CEV, NJB, TNT], ‘unseen’ [BAGD; NJB, TNT], ‘what cannot be seen’ [LN], ‘who cannot be seen’ [SSA; CEV].
c. πρωτότοκος (LN 10.43; 13.79; 87.47) (BAGD 2.a. p. 726): ‘firstborn’ [BAGD, Herm, LN (10.43), Lns, NIC, NTC, WBC; CEV, KJV, NAB, NASB, NIV, NJB, NRSV], ‘existing first’ [LN (13.79)], ‘existing before’ [LN (13.79)], ‘superior to’ [LN (87.47)]. This noun is also translated as a verb phrase: ‘to take precedence’ [TNT], ‘to rank above’ [SSA]; as a noun phrase followed by an adjective: ‘first-born Son, superior’ [TEV]; by a clause: ‘his is the primacy’ [REB], ‘he existed before God made anything at all and is supreme’ [NLT].
d. κτίσις (LN 1.4; 42.38) (BAGD 1.b.α. p. 455): ‘creation’ [Herm, LN, Lns, NIC, WBC; CEV, NASB, NIV, NJB, NLT, NRSV, REB], ‘creature’ [BAGD, LN (42.38), NTC; KJV, NAB], ‘created thing’ [BAGD; TEV], ‘what was made’ [LN (1.4)], ‘what has been created’ [LN (42.38)], ‘which has been created’ [SSA], ‘created universe’ [TNT], ‘universe’ [LN (1.4)].
QUESTION—How is this verse related to the preceding?
1. After stating in 1:14 what we have because of Christ, Paul now describes Christ [Alf, Herm, Lns, My, NIC], who he is [Alf, Lns, My] and his rank [Lns, My, NIC] and work [Lns].
2. It is the reason for 1:14 [Ea]: through him we are redeemed and our sins are forgiven, because he is the image of the invisible God.
QUESTION—To what time does ὅς ἐστιν εἰκὼν τοῦ θεοῦ τοῦ ἀοράτου ‘who is the image of the invisible God’ refer?
1. It refers to the present time, to Christ in his glorified state [Alf, EGT, ICC, Lg, My, TNTC].
2. It refers to all eternity [BAGD, Lns, Lt, NTC, WBC], to what Jesus is and always has been and not only to his time here on earth, in that his being the image of God was already a reality before the world was created [Lns].
3. It refers to the time when Christ was here on earth [Mrt, NIC, TH].
4. The main reference is to when Christ was here on earth and to his present work at God’s right hand, but it also includes his creation of the universe and preservation of it [Ea].
QUESTION—What is meant by αὀράτου ‘invisible/unknown’?
1. It means something which has never been seen [EG, NTC] and cannot be seen [Ea, EG, SSA, TH]. It means physically invisible [Mrt, SSA]. God is invisible because he is spirit; he is not of a material substance [Mrt].
2. It means unable to be known [EGT].
3. It means both physically invisible and unable to be known [Alf, Lt].
QUESTION—What is meant by εἰκὼν τοῦ θεοῦ τοῦ ἀοράτου ‘image of the invisible/unknown God’?
It means that Jesus represents God visibly [Alf, Ea, EG, ICC, Lns, Mrt, My, NIC, NTC, SSA, TH, WBC; NLT, TEV] and exactly [Ea, EG, Mou, Mrt, My, NIC, SSA, TNTC, WBC] to people [NTC, TH], to believers [EGT, Lns, Mrt]. It means that he is God [Ea, Herm, Lg, Lns, Mrt, My, NTC, TNTC] and that he reveals God to us, by virtue of which we see the invisible God [Ea, ICC, Lg, Lns, Mou, Mrt, My, NIC, NTC, WBC]. It means that Jesus is the revelation of God, that he makes God known [Herm, Lt], and it refers to the fact that Jesus is sovereign [Herm]. Because Jesus is the eternal Son of God he is God, and as such he makes God and God’s majesty visible to us by means of our faith [Lns]. He reveals the nature of God, that about God which is invisible [Alf, NIC]. He is so much like the Father that he makes the Father known to Christians [EGT]. We can see God to a certain extent in nature and in people, who are created in his image, but it is only in Jesus that we see God perfectly [Mou]. At the second coming the whole world will see Jesus’ visible revealing of God’s majesty [My].
QUESTION—What is meant by πρωτότοκος ‘firstborn’?
It was a title of the Messiah [ICC, Lt, NIC, SSA, TNTC]. It means that Jesus is the eternal Son of God and thus is God [Lns] and not a created being [EG, Lns]. It does not refer to Jesus’ birth as a human being [Alf, TH], but to his relation to God as the eternal Son of God and his heir [TH]. ‘Image of the invisible God’ refers to Christ’s relation to God, and ‘firstborn of all creation’ to his relation to the creation [Lg, Lt, My, WBC].
QUESTION—What is meant by πάσης κτίσεως ‘all creation’?
1. It means all creatures [BAGD, EGT, Lns, My, NTC; KJV, NAB], all created things [BAGD, EGT, ICC, SSA; TEV], including the new creation [SSA], every kind of creature, angels and people [Lg].
2. It means creation as a whole [Alf, Ea, Lt; TNT], the universe [Ea, Mou].
QUESTION—What is meant by πρωτότοκος πάσης κτίσεως ‘firstborn of all creation’?
1. It means that Jesus ranks above all creation [Ea, EGT, Herm, Lns, SSA; REB] and is its Lord [Herm], in that he existed before creation and it was through him that all things were created [Herm]. God the Father has given the rulership of the universe to Jesus and all of our dealings are with him as the Father’s representative [Ea]. He is Lord and ruler [Ea, EGT].
2. It means that Jesus existed before anything was created [ICC, Lg, My]. He is higher than creation [My].
3. It means both that Jesus ranks above all creation and that he existed before all creation [Alf, EG, Lt, Mou, Mrt, NIC, NTC, TH, TNTC, WBC; NLT]. He is distinct from creation [Lt, Mou, NIC, NTC, TH, WBC] and it was through him that all things were created [Lt, Mou, NIC, NTC]. He is the Lord of creation [Lt, NIC, WBC]. He is heir of all things and ruler of all things [Lt, NIC, NTC].
 King, M. (2008). An Exegetical Summary of Colossians (2nd ed., pp. 49–51). Dallas, TX: SIL International.