'Joined' in the Bible

For the Lord will have mercy on Jacob, and will again make Israel his special people, and will put them in their land; and the man from a strange country will take his place among them and be joined to the family of Jacob.

And let not the man from a strange country, who has been joined to the Lord, say, The Lord will certainly put a division between me and his people: and let not the unsexed man say, See, I am a dry tree.

And as for those from a strange country, who are joined to the Lord, to give worship to him and honour to his name, to be his servants, even everyone who keeps the Sabbath holy, and keeps his agreement with me: