An unpublished Villa-Lobos letter

From the Brazilian site "Glorias: Documentos Raros" comes this punning letter from Villa-Lobos to his friend and pupil "Didi", from 1956.

 

Is it possible?

Di, in place of Do.

Do, in place of Di.

H. Villa-Lobos

 

[from Google Translate:]

Didi,
For those who are willing to follow difficult but glorious work like that you learn and practice at your house but again we can say, since this work is have the purest and most beautiful of all philosophies. But never be repeated too often, as I do now, citing this small piece of the Proverbs of Solomon: "Guard your heart more than all things, for it come the fruits of life."
08.01.46, Pará