Ishmael’s House is the house to which Nephi and those with him went up in order to speak with Ishmael. They “did gain favor in the sight of Ishmael,” and spoke to him “the words of the Lord” (1 Nephi 7:4).
The Lord softened the heart of Ishmael and “also his household.” Ishmael’s household then traveled with Nephi’s group “down into the wilderness to the tent of our father” (1 Nephi 7:5).