I am not אהיה for you

Hosea 1:8, 9

ותגמל את לא-רחמה ותהר ותלד בן. ויאמר קרא שמו לא-אמי כי אתם לא אמי ואנכי לא-אהיה לכם.

After she weaned Lo-Ruhama, she conceived and bore a son.  Then He said, 'Name him Lo-Ammi, because you are not my people, and I am not Ehieh for you.'

Anybody familiar with the oracles of Hosea knows that the first chapter relates the story of his experiences with an unfaithful wife, Gomer, whose conduct became a parable for the unfaithfulness of Israel.  Within the first eight verses of chapter 1, Hosea's wife produced three children all of whom were the result of adulterous relations.  Following the birth of each child, YHWH commanded Hosea to give that a name that reflected God's response to the faithlessness of Israel.  The third child was named Lo-Ammi, and the explanation for the significance of this name contains an interpretive problem.  The ways that various translations deal with this textual problem are as follows:

NASB – Name him Lo-Ammi, for you are not My people, and I am not your God.

LXX, Vg, Syr – Name him Not-My-People, because you are not My people, and I am not for you.

Targum – Name him Lo-Ammi for the reason that you are not My people; you abstained from establishing My instruction, the Word (מימרי) has not been your support.

There is no hint of any textual problem in the Masoretic tradition, and the LXX, Vg, and Syriac text all support the Hebrew text as it stands.  Only the Targum expands the text to make the rationale for the name more explicit.  However, the meaning 'I am not for you' does not make particularly good sense.  Perhaps the prophet was trying to make a somewhat more specific point by his particular choice of words.  Consider the following.  In Exodus 3:13, 14 Moses responded to God's command to return to Egypt with this excuse:

Them Moses said to God, 'Behold, I am going back to the sons of Israel, and I will say to them, "The God of your fathers has sent me to you."  Then they will say to me, "What is name?"  What do I say to them?'  Then God said to Moses, 'אהיה אשר אהיה. This is what you say to the sons of Israel: 'אהיה sent me to you.'

Effectively, the statement in Hosea 1:9 is a negation of the common statement, 'You will be My people, and I will be your God,' but instead of using the word for God he used the descriptive term for God's name that had been given to Moses.  Because of their constant unfaithfulness, the God no longer regarded that generation of Israelites as His people, and he would no longer be אהיה for them.  It was the end of the line for this generation of Israelites, but as the rest of the book points out, YHWH would woo back and restore a subsequent generation who would be faithful.