Isaiah 48:12 Hearken unto me, O Jacob and Israel, my called; I am he; I am the first, I also am the last. 13 Mine hand also hath laid the foundation of the earth, and my right hand hath spanned the heavens: when I call unto them, they stand up together. 14 All ye, assemble yourselves, and hear; which among them hath declared these things? The LORD hath loved him: he will do his pleasure on Babylon, and his arm shall be on the Chaldeans. 15 I, even I, have spoken; yea, I have called him: I have brought him, and he shall make his way prosperous. 16 Come ye near unto me, hear ye this; I have not spoken in secret from the beginning; from the time that it was, there am I: and now the Lord GOD, and his Spirit, hath sent me.
God goes to great lengths in these passages to make it clear that He is speaking firsthand. God is the speaker and yet the speaker has been sent forth by God and His Spirit. It is a great mystery... but your beef is with Him... we simply take Him at His Word.
A) That is not a good translation of the Hebrew. This is better. מֵעֵת הֱיוֹתָהּ, שָׁם אָנִי; וְעַתָּה, אֲדֹנָי יְהוִה שְׁלָחַנִי--וְרוּחוֹ. {פ}
That is the way it is written in the Hebrew. The last word is ruach- spirit, and second to the last word is shalach-to send me...put it together you have:
16....and now, the Lord God has sent me, and His spirit. טז. 17. So said the Lord, your Redeemer, the Holy One of Israel, "I am the Lord your God, Who teaches you for your profit, Who leads you by the way you should go.
IN CONTEXT, the person speaking changes, this is something that Isaiah does on several occasions. And remember, in the original Isaiah, there are no verses and chapters, so it makes more contextual sense when you incluse verse 17. So, verse 16 is Isaiah speaking of himself...The LORD G-d has sent me (Isaiah) and his spirit (of prophecy).
B) Your rendering is also poor hermeneutics. A person must use passages in the light ie clear, to shed understanding on those that may not be so clear. At least a dozen times in Isaiah alone, G-d say he is alone, no other, no other savior. So, then why try to use a passage like 48:16 and twist the content to shoe-horn a meaning not there and create doctrine? If you simply take him at his word as you claim, you would rest upon the dozens of clear passsages where G-d says he is a perfect, solitary unity. ANY other attempt to create doctrine of a composite god stands against G-d.
They tell me Mohammed (PBUH) went to heaven too... And he got to bring his HORSE! There sure are a lot of little godlings around promising salvation. Let’s make sure we never take the Lord’s actual, firsthand commandments too seriously, shall we? Perhaps Saul of Tarsus can clarify the matter... Or some other mortal. Maybe you? Or are you a Messenger, too?