In the Genesis Flood narrative, God shut the door of Noah’s Ark.
Genesis 7:16 says that after Noah, his family, and the animals entered the Ark, “the LORD shut him in.” The statement appears at the transition from preparation to the arrival of the Flood and emphasizes divine protection of those inside.
Noah is instructed to build the Ark, gather his family, and bring in the animals, but the closing action is attributed to God. This detail is separate from the Ark’s construction, its waterproofing, and Noah’s later actions during the voyage. The text does not describe Noah personally closing the door.
The surrounding passage presents the animals entering according to their kinds and Noah entering with his household. The phrase about the door is therefore a narrative detail with theological importance, while also being a precise answer to the question of who performed the final closing action.