But men should be individually certain about this, that they are the people of God, or members of the church. Above all things this faith is necessary which firmly apprehends the following syllogism. The whole people of God is blessed, holy, pleasing, and acceptable to God in such a way that it cannot be torn from the hands of God. We are the people of God. Therefore God exercises care for us. The major premise is eminently true, because even the death and blood of the saints are precious in the sight of the Lord (cf. Ps. 116:15); all they do and suffer is pleasing to God. On the contrary, their errors and lapses have been covered and forgiven, as Ps. 32:1 testifies.
Luther’s works, vol. 6: Lectures on Genesis: Chapters 31-37 p 9