Immanuel means ‘God with us,’ and Matthew 1:23 applies the name to Christ. Shearjashub’s name speaks into Israel’s distress in Isaiah 7. God goes through our distress with us, and God unites his people to the coming child.
Ahaz faces Syria and Israel, and Isaiah prophesies into that crisis. Chapters 7-12 form the book of Immanuel, and its children carry the message. Isaiah’s son Shearjashub bears a name that means ‘a remnant shall return.’
Joseph’s dream and the debated meaning of Isaiah 7:14 both converge on a single claim: the name Jesus is the same name as Joshua, and it means the same thing here. Isaiah’s own sign, the remnant child Shear-jashub, already anticipates a salvation that comes through apparent weakness rather than visible strength. The name itself, read this way, is already a sermon.