Gerhard and Walther

When we give thanks to God we are doing nothing other than that we acknowledge in our heart and confess with the mouth that everything good that we possess has not been bestowed up9on us casually or by our own wisdom and power, but only and solely from the kind goodness of God the Most High by which He also is sanctified by us and others.—Johann Gerhard, Schola Pietatis III:274

A Church that wants to be a Christian church maintains that the faith it confesses is the true one. A church that lays no such claim renounces itself as a branch of the true Christian faith. Yet not every church that claims to have the true faith actually possesses it. Everything depends on the foundation on which its doctrine and faith are built.—C. F. W. Walther, God Grant It!, p. 579.