By faith he dwelt in the promised land as a stranger in a foreign country. He lived in tents, as did Isaac and Jacob, who were heirs with him of the same promise. ... All these people died in faith, without having received the things they were promised. However, they saw them and welcomed them from afar. And they acknowledged that they were strangers and exiles on the earth. Now those who say such things show that they are seeking a country of their own. If they had been thinking of the country they had left, they would have had opportunity to return. Instead, they were longing for a better country, a heavenly one. Therefore God is not ashamed to be called their God, for He has prepared a city for them.
If indeed they have escaped the corruption of the world through the knowledge of our Lord and Savior Jesus Christ, only to be entangled and overcome by it again, their final condition is worse than it was at first. It would have been better for them not to have known the way of righteousness than to have known it and then to turn away from the holy commandment passed on to them. Of them the proverbs are true: “A dog returns to its vomit,” and, “A sow that is washed goes back to her wallowing in the mud.”