The apostles never said that Jesus was "a God", only "God".
No, that is the point they called Him Lord.
The grace of the Lord Jesus Christ and the love of God and the fellowship of the Holy Spirit be with you all. 2nd Corinthians 13:14
And when Jesus was baptized, immediately he went up from the water, and behold, the heavens were opened to him, and he saw
the Spirit of God descending like a dove and coming to rest on him; and behold, a voice from heaven said, “
This is my beloved Son, with whom I am well pleased.” Matthew 3:16-17
Yet for us there is one God, the Father, from whom are all things and for whom we exist, “and” one Lord, Jesus Christ, through whom are all things and through whom we exist. 1st Corinthians 8:6
"Do not cling to me, for I have not yet ascended to the Father. But go and tell my brothers,
'I am ascending to my Father and your Father, to my God and your God'" John 20:17
About the ninth hour Jesus cried out with a loud voice, saying, “ELI, ELI, LAMA SABACHTHANI?” that is, “
MY GOD, MY GOD, WHY HAVE YOU FORSAKEN ME?” Matthew 27:46
According to the foreknowledge of God the Father, in the sanctification of the Spirit, for obedience to Jesus Christ and for sprinkling with his blood: May grace and peace be multiplied to you. 1st Peter 1:2
But the Helper, the Holy Spirit, whom the Father will send in my name, he will teach you all things and bring to your remembrance all that I have said to you. John 14:26
Peace be to the brethren, and love with faith, from
God the Father and the Lord Jesus Christ. Grace be with all those who
love our Lord Jesus Christ with a love incorruptible. Ephesians 6:23-24
May God himself, the God of peace, sanctify you through and through. May your whole spirit, soul and body be kept blameless at the coming of our Lord Jesus Christ. The one who calls you is faithful, and he will do it. Brothers and sisters, pray for us.
Greet all God’s people with a holy kiss. I charge you before
the Lord to have this letter read to all the brothers and sisters.
The grace of our Lord Jesus Christ be with you. 1st Thessalonians 5:23-28
Now may the God of peace, who through the blood of the eternal covenant brought back from the dead our Lord Jesus, that great Shepherd of the sheep, equip you with everything good for doing his will, and may he work in us what is pleasing to him, through Jesus Christ, to whom be glory for ever and ever. Amen.
Anyone who goes too far and does not abide in the teachings of Christ, does not have God; the one who abides in the teachings, he has both the Father and the Son. 2nd John 1:9
And I will ask the Father, and he will give you another Helper, to be with you forever, even the Spirit of truth, whom the world cannot receive, because it neither sees him nor knows him. You know him, for he dwells with you and will be in you. John 14:16-17
But
when the Helper comes, whom I will send to you from the Father, the Spirit of truth, who proceeds from the Father, he will bear witness about me. John 15:26
4 There is one body and one Spirit, just as also you were called in one hope of your calling; 5
one Lord, one faith, one baptism, 6 one God and Father of all who is over all and through all and in all.
Ephesians 4:4-6
To our God and Father be glory for ever and ever. Amen. Greet all God’s people in Christ Jesus. The brothers and sisters who are with me send greetings. All God’s people here send you greetings, especially those who belong to Caesar’s household. The grace of the
Lord Jesus Christ be with your spirit. Amen. Philippians 4:20-23
They never demoted God the Father.
At times they took creation away from God the Father and said Yeshua created everything. But just at times.