Not a wt-Jw:
I must say that I am happy for all the various scholars we have available to consult through many translations. Relying on just one translation for the wording is not sufficient. Rather, when problems arise, many should be consulted.
In this case, avoiding the NWT because you may think it tainted in favor of the Wt church's viewpoint - I went to the most excellent translation by the Catholic church, and others:
Here are three translations:
New Jerusalem Bible, Catholic:
28'Be on your guard for yourselves and for all the flock of which the Holy Spirit has made you the guardians, to feed the Church of God which he bought with the blood of his own Son.
An American Bible, Online - recent translation:
28 So now; Pay attention to yourselves and to the whole flock that the Holy Breath [of God] has appointed you to watch over and shepherd… this congregation of God, which He purchased with the blood of [His own Son].
ASV: (also a very known and good translation)
28 Take heed unto yourselves, and to all the flock, in which the Holy Spirit hath made you bishops, to feed the church of the Lord which he purchased with his own blood.
Then you have other translations repeating somewhat what your translation said.
What it boils down to then is that we must look at what is taught about Christ, about God, and let a harmonic interpretation guide us.
Try reading in the KJV since you are using that one, the first chapter of Revelation.
1. God gives Christ the revelation
4-7. Jesus and God mentioned totally separate
Jesus is shown to view God, the Father, as his God
4 John to the seven churches which are in Asia: Grace be unto you, and peace, from him which is, and which was, and which is to come; and from the seven Spirits which are before his throne; 5 And from Jesus Christ, who is the faithful witness, and the first begotten of the dead, and the prince of the kings of the earth. Unto him that loved us, and washed us from our sins in his own blood, 6 And hath made us kings and priests unto God and his Father; to him be glory and dominion for ever and ever. Amen.
9. the word of God and the testimony of Jesus -- separated
8. !! Here you need to consult other translations, the ASV again?,
it says Lord God, not used for Jesus!
"8 I am the Alpha and the Omega, saith the Lord God, who is and who was and who is to come, the Almighty."
Why try to make Jesus more than he is?
He is whom we live for, whom we die for.
He is our only master, our Lord.
He is the one who resurrects us.
The evidence when collected about who Jesus is - is not ambiguous.
That doesn't mean that the Wt's teachings about Jesus are appropriate - they do not give him the honor he deserves. They do not live for Christ but for the Father, Jehovah. This is not what was ordained.
Through our obedience to Christ, our preaching of Christ we do God's will since that is surely what Christ revealed. But we must live for Christ. We pray to the Father, and we pray to the son. The Father is worshiped, and the son as our Lord, our shepherd, our caretaker, our teacher, is approached as our master for assistance and loving care.
We confess Christ - not the Father in that same way - that is not what we were instructed to do. Christ is our ransom, the way to God, but we are (should be) in Christ to be reconciled with God.