John 20.28 is no proof that Jesus is god because god and lord are in the nominative case and not the vocative case. Every time Jesus is addressed as Lord in the bible he is addressed in the vocative case of lord (kurie) and never in the nominative case of Lord (kurios)
I think you may be getting rather confused.
Vocative case is used when addressing someone directly. Nominative case when their name or title is the subject of a particular sentence or phrase.
Lord, bless me. Vocative case.
The Lord be praised. Nominative case.
Therefore it is right that the vocative is used when addressing the Lord by name, the nominative when making a statement of some kind, without addressing him.
I am not sure what point you are trying to make, but this does not prove anything other than that the Scriptures follow appropriate grammatical rules.
Therefore, Thomas was talking about god and lord to Jesus not addressing Jesus as god and lord. So how was Thomas talking about god and lord to Jesus? He was uttering an exclamation, just as anyone would in that situation. Or it was an incomplete sentence, after all we all utter incomplete sentences. Some scholars believe it was an incomplete sentence, I lean more towards an exclamation but don't rule out an incomplete sentence.
An exclamation in the vocative case is still addressed TO someone.
O God, save and preserve me! is vocative.
God Almighty! Vocative.
Good God! Vocative.
Jesus Christ! Vocative.
Gordon Bennet! Vocative.
Also, it is asserted by scholars that the nominative is used for the vocative, but I have as yet to see even one clear cut example of the nominative being used for the vocative, so I'm not sure that is correct. Even in mark where Mark uses the nomative when quoting Jesus "my god,my god why has thou forsaken me",
'My God, My God, why hast thou forsaken me' is vocative. I think you are getting a bit confused here. This is a direct quotation from the psalms, where 'My God' will be Hebrew, but still vocative (if they have such a case, that is.)
it is possible that Jesus uttered one in hebrew, then one in aramaic, and that the utterances where different.
Not if he was quoting Psalm 22, as indeed he was. He would have quoted it in Hebrew. As with Judaism today, the Scriptures are read or quoted in Hebrew, interpreted in the vernacular. We have evidence of this from the gospels, because only the scholars standing around knew what he was saying. The majority of aramaic speakers would not have understood Hebrew, even if they could read it.
So, here, in full, is what the Lord was referencing, when he was on the cross. It is addressed to God, and uses the vocative case extensively (underlined).
Psalm 22
1 My God, my God, why hast thou forsaken me?
Mt. 27.46 · Mk. 15.34
Why art thou so far from helping me,
and from the words of my roaring?
2 O my God, I cry in the daytime, but thou hearest not;
and in the night season, and am not silent.
3 But thou
art holy,
O thou that inhabitest the praises of Israel.
4 Our fathers trusted in thee:
they trusted, and thou didst deliver them.
5 They cried unto thee, and were delivered:
they trusted in thee, and were not confounded.
6 But I
am a worm, and no man;
a reproach of men, and despised of the people.
7 All they that see me laugh me to scorn:
they shoot out the lip, they shake the head,
Mt. 27.39 · Mk. 15.29 · Lk. 23.35 saying,8 He trusted on the L[SIZE=-1]ORD[/SIZE]
that he would deliver him:
let him deliver him, seeing he delighted in him.
Mt. 27.43
9 But thou
art he that took me out of the womb:
thou didst make me hope
when I was upon my mother's breasts.
10 I was cast upon thee from the womb:
thou
art my God from my mother's belly.
11 Be not far from me; for trouble
is near;
for
there is none to help.
12 Many bulls have compassed me:
strong
bulls of Bashan have beset me round.
13 They gaped upon me
with their mouths,
as a ravening and a roaring lion.
14 I am poured out like water,
and all my bones are out of joint:my heart is like wax;it is melted in the midst of my bowels.
15 My strength is dried up like a potsherd;
and my tongue cleaveth to my jaws;and thou hast brought me into the dust of death.
16 For dogs have compassed me:
the assembly of the wicked have inclosed me:they pierced my hands and my feet.
17 I may tell all my bones:
they look
and stare upon me.
18 They part my garments among them,
and cast lots upon my vesture.
Mt. 27.35 · Mk. 15.24 · Lk. 23.34 · Joh. 19.24
19 But be not thou far from me,
O L[SIZE=-1]ORD[/SIZE]:
O my strength, haste thee to help me.
20 Deliver my soul from the sword;
my darling from the power of the dog.
21 Save me from the lion's mouth:
for thou hast heard me from the horns of the unicorns.
22 I will declare thy name unto my brethren:
in the midst of the congregation will I praise thee.
Heb. 2.12 23 Ye that fear the L[SIZE=-1]ORD[/SIZE], praise him;
all ye the seed of Jacob, glorify him;and fear him,
all ye the seed of Israel.
24 For he hath not despised nor abhorred the affliction of the afflicted;
neither hath he hid his face from him;but when he cried unto him, he heard.
25 My praise
shall be of thee in the great congregation:
I will pay my vows before them that fear him.
26 The meek shall eat and be satisfied: they shall praise the L[SIZE=-1]ORD[/SIZE] that seek him:your heart shall live for ever.
27 All the ends of the world shall remember and turn unto the L[SIZE=-1]ORD[/SIZE]:
and all the kindreds of the nations shall worship before thee.
28 For the kingdom
is the L[SIZE=-1]ORD[/SIZE]'s: and he
is the governor among the nations.
29 All
they that be fat upon earth shall eat and worship: all they that go down to the dust shall bow before him:and none can keep alive his own soul.
30 A seed shall serve him; it shall be accounted to the Lord for a generation.
31 They shall come, and shall declare his righteousness unto a people that shall be born, that he hath done
this.
Psalms 22. The Holy Bible: King James Version.