‘(…) Rabbi Jonathan Sacks comments in his The Great Partnership: Science, Religion, and the Search for Meaning (pp. 64-65):
‘Who are you?’ asks Moses. God replies, cryptically, Ehyeh asher ehyeh. This was translated into Greek as ego eimi ho on, and into Latin as ego sum qui sum, meaning ‘I am who I am’, or ‘I am he who is’. The early and medieval Christian theologians all understood the phrase to be speaking about ontology, the metaphysical nature of God’s existence. It meant that he was ‘Being-itself, timeless, immutable, incorporeal, understood as the subsisting act of all existing’. Augustine defines God as that which does not change and cannot change. Aquinas, continuing the same tradition, reads the Exodus formula as saying that God is ‘true being, that is being that is eternal, immutable, simple, self-sufficient, and the cause and principal of every creature’. But this is the God of Aristotle and the philosophers, not the God of Abraham and the prophets. Ehyeh asher ehyeh means none of these things. It means ‘I will be what, where, or how I will be’. The essential element of the phrase is the dimension omitted by all the early Christian translations, namely the future tense. God is defining himself as the Lord of history who is about to intervene in an unprecedented way to liberate a group of slaves from the mightiest empire of the ancient world and lead them on a journey towards liberty.
Rabbi Sack goes on to describe exactly who is the character Yahweh in the Hebrew Bible:
Far from being timeless and immutable, God in the Hebrew Bible is active, engaged, in constant dialogue with his people, calling, urging, warning, challenging and forgiving. When Malachi says in the name of God, ‘I the Lord do not change’ (Malachi 3: 6), he is not speaking about his essence as pure being, the unmoved mover, but about his moral commitments. God keeps his promises even when his children break theirs.
From one of the most prominent Jews in the world, it would be hard to dismiss his understanding as flawed. The Hebrew idea of God is not one of the Greek philosophers. The Hebrew position starts with the face value testimony found in the Bible. This is echoed by Christian Old Testament Scholar Walter Brueggemann and Secular Harvard Professor Christine Hayes. Both these individuals recognize that the Hebrew religion is in essence relational. Yahweh is not the timeless, immutable, and omniscient god of Plotinus, be relentlessly modifying His actions in response to human beings. This is the language of the Bible.
Yahweh began in earnest curiosity as mankind first budded onto the scene. This curiosity quickly morphed to regret as mankind fell into utter depravity. After a near universal destruction, God’s resignation towards a sinful creation allowed mankind to again replenish the Earth. Through dedication, God sought to reconcile the world to Him, choosing a man and a nation to act as His people. Through fierce anger, God punishes their oppressors. Through hope and mercy, God liberates them and brings them to their own land. In jealousy, God wants to destroy them time and time again for their rebellion. But through reason, God spares His wayward people.
This nation continually disappoints God. God grows frustrated and exasperated. God tries all types of blessings and curses to sway them, but they do not listen. God cycles through stages of sorrow, depression, anger, vindictiveness, and downright indifference. The world has at one time collectively failed God, and now God is suffering by fault of His own people.
Lastly, God sends His son to liberate His people once again. But once again this is met with rejection. A promise of a Kingdom on Earth is met with widespread disbelief. This results in a previously unseen mission to the Gentiles. Paul declares that God has made this people equal to the surrounding nations in a last ditch effort to provoke them to jealousy. After all these things are done, Yahweh will return to Earth and establish an everlasting Kingdom of God. Yahweh will rule from Jerusalem and all the nations will be subject to God.
source: Christopher Fisher, “Apologetics Thursday – Hellenistic or Hebrew” (godisopen).