A non-Israelite who resides among Israel — not merely passing through, but dwelling as a resident alien without full civic rights, land inheritance, or tribal membership. The gēr was socially vulnerable, dependent on the hospitality of the community, and therefore specially protected by Mosaic law alongside widows and orphans.
The theology of the gēr is rooted in Israel's own experience: 'You shall not oppress a sojourner; you know the heart of a sojourner, for you were sojourners in the land of Egypt' (Exod 23:9). This experiential ethic drives over 90 OT laws protecting aliens — they must be treated justly (Deut 1:16), loved (Deut 10:19), allowed to rest on Sabbath (Exod 20:10), fed from tithes (Deut 14:29), and included in worship festivals (Deut 16:14). The theological punch is that Israel itself is a sojourner before God — 'the land is mine; for ye are strangers and sojourners with me' (Lev 25:23). This radical leveling — everyone is a gēr before God — anticipates the NT vision where 'there is neither Jew nor Greek' (Gal 3:28).