Letter XXVI. 1988 To Cæsarius, brother of Gregory . 1989 Thanks to God for shewing forth His wonderful power in your person, and for preserving you to your country and to us your friends, from so terrible a death.  It remains for us not to be ungrateful, nor unworthy of so great a kindness, but, to the best of our ability, to narrate the marvellous works of God, to celebrate by deed the kindness which we have experienced, and not return thanks by word only.  We ought to become in very deed what I, grounding my belief on the miracles wrought in you, am persuaded that you now are.  We exhort you still more to serve God, ever increasing your fear more and more, and advancing on to perfection, that we may be made wise stewards of our life, for which the goodness of God has reserved us.  For if it is a command to all of us “to yield ourselves unto God as those that are alive from the dead,” 1990 how much more strongly is not this commanded them who have been lifted up from the gates of death?  And this, I believe, would be best effected, did we but desire ever to keep the same mind in which we were at the moment of our perils.  For, I ween, the vanity of our life came before us, and we felt that all that belongs to man, exposed as it is to vicissitudes, has about it nothing sure, nothing firm.  We felt, as was likely, repentance for the past; and we gave a promise for the future, if we were saved, to serve God and give careful heed to ourselves.  If the imminent peril of death gave me any cause for reflection, I think that you must have been moved by the same or nearly the same thoughts.  We are therefore bound to pay a binding debt, at once joyous at God’s good gift to us, and, at the same time, anxious about the future.  I have ventured to make these suggestions to you.  It is yours to receive what I say well and kindly, as you were wont to do when we talked together face to face. 1988     Placed in 368. 1989     Cæsarius was the youngest brother of Gregory of Nazianzus.  After a life of distinguished service under Julian, Valens, and Valentinian, he was led, shortly after the escape narrated in this letter, to retire from the world.  A work entitled Πύστεις , or Quæstiones ( sive Dialogi ) de Rebus Divinus , attributed to him, is of doubtful genuineness.  Vide D.C.B. s.v .  The earthquake, from the effects of which Cæsarius was preserved, took place on the tenth of October, 368.  cf . Greg. Naz, Orat . x. 1990     Rom. vii. 13 .