Related by his then fiancée, Maria von Wedemeyer:
Dietrich was moved to the Gestapo prison in October 1944. It was then impossible to obtain visitation permits, and it is improbable that any of my letters reached him there. When the prison was badly damaged during an air raid in February he was moved out of Berlin and my attempts to find him in either Dachau, Buchenwald, or Flossenburg failed. In his last letter to me at Christmas, 1944, he wrote:
These will be quiet days in our homes. But I have had the experience over and over again that the quieter it is around me, the clearer do I feel the connection to you. It is as though in solitude the soul develops senses which we hardly know in everyday life. Therefore I have not felt lonely or abandoned for one moment. You, the parents, all of you, the friends and students of mine at the front, all are constantly present to me. Your prayers and good thoughts, words from the Bible, discussions long past, pieces of music, and books, — [all these] gain life and reality as never before. It is a great invisible sphere in which one lives and in whose reality there is no doubt. If it says in the old children’s song about angels: ‘Two, to cover me, tow, to wake me,’ so is this guardianship, by good invisible powers in the morning and at night, something which grown ups need today no less than children. Therefore you must not think that I am unhappy. What is happiness and unhappiness? It depends so little on the circumstances; it depends really only on that which happens inside a person. I am grateful every day that I have you, and that makes me happy (19 December 1944).
From Dietrich Bonhoeffer, “Letters and Papers from Prison”, New York, NY: Macmillan Publishing Co, ©1953, 1967, 1971, Enlarged Edition, pp 418–419.