Who Is Yahweh
The short answer
Yahweh is not a title or a job description. It is a personal name — the name God uses for self-introduction in the Bible. In Exodus 6, God tells Moses, "I am Yahweh," and adds something surprising: Abraham, Isaac, and Jacob did not actually know God by this name. As John Goldingay explains, the ancestors were genuinely in relationship with this same God, but the name itself belongs to a new moment. God is about to do something new — bring Israel out of Egypt — and the new name marks a new stage in the relationship. From this point on, God frequently opens a speech with that self-introduction, the way a person leads with their name.
So who is Yahweh in the Bible? A name only tells you so much; character shows in action, and in what a person will hear. That is where Lamentations comes in. The first poem grieves over Jerusalem's destruction and acknowledges, remarkably, that Yahweh himself brought the judgment — and that the city's rebellion made the judgment just. The poem does not accuse Yahweh of going too far. Yet it does not fall silent either. It pleads with Yahweh to look at the suffering and to act against the city's devastators.
Put the two passages together and a portrait emerges. Yahweh is a God who introduces himself by name, entering into a real, personal relationship with a people. And Yahweh is a God who can be addressed by that name even in disaster — even when the disaster came from his own hand. Accepting that God's action was just does not close the conversation; it opens a different kind of prayer. The named God remains a God you can still talk to, and ask for something different.
What scholars say
These two passages from John Goldingay answer the question from both directions: the first explains why "I am Yahweh" marks a new name for a new stage in God's relationship with Israel, and the second shows how Lamentations 1 accepts the justice of Yahweh's judgment on Jerusalem while still pleading with him to act.
““I am Yahweh,” God says. In Genesis, God made that declaration to Abraham and Jacob, but Genesis did not quite mean this literally. God here notes that the actual name Yahweh was not revealed to them. There was not untruth involved in portraying them as in relationship with Yahweh, because Yahweh really was relating to them, but Yahweh did not literally use that name. As Exodus 3 described more fully, there is now a new name to go with a new stage in God’s relationship with them and a new stage in God’s activity among them. Henceforth in Exodus and elsewhere, God often begins speaking with this self-introduction, “I am Yahweh.” The implication then will be not that they do not know who God is.”
“The first poem grieves over the destruction of Jerusalem by the city's adversaries and by Yahweh, laments over the ongoing anguish of people who identify with the city, recognizes that the city's rebellion justified Yahweh's action, but pleads with Yahweh to look at its suffering and finally to take action against its devastators. It thus does not complain about Yahweh's action, though it does begrudge the action of its human devastators, nor does it imply that the calamity was excessive. The description "lament" is more appropriate for Lam 1 than it is for the other poems and for most of the so-called "lament psalms," which are characterized more by protest than lament. But accepting the propriety of Yahweh's action does not rule out pleading with Yahweh to take a different sort of action.”
What it means for you
A name is an invitation. When God says "I am Yahweh," it means God wants to be known personally, not managed from a distance. For a reader today, that changes what prayer can be: you are not addressing a vague force but someone who has introduced himself.
Lamentations adds a harder, more freeing lesson. Even when you believe your suffering is somehow deserved, or when God seems to be the one behind your loss, you have not lost the right to speak. Honest grief and continued pleading can live in the same prayer. The God who gave his name stays reachable by it.
In context
In Exodus 6, God speaks to Moses at a low point: Moses has confronted Pharaoh, and things have only gotten worse for the Israelites. God responds by declaring "I am Yahweh" and promising deliverance, connecting this new name to a new act of rescue that the ancestors never saw. Lamentations 1 sits at the other end of Israel's story — a poem of grief written in the aftermath of Jerusalem's destruction, when the people who identified with the city were living with ongoing anguish and asking what could still be said to Yahweh.