Faithfulness.

But Ruth said: “Entreat me not to leave you, Or to turn back from following after you; For wherever you go, I will go; And wherever you lodge, I will lodge; Your people shall be my people, And your God, my God. Where you die, I will die, And there will I be buried. The Lord do so to me, and more also, If anything but death parts you and me.” (Ruth 1:16-17)