In December 1941, Portinari wrote a letter to his friend Queiroz Lima:
"...We are still working night and day. I have started the last mural. People here wonder at this speedy pace, but I have been painting murals for four years. I think it is my capolavôro. ..."
"...MacLeish is a fabulous man and he is very satisfied. The public may find the work odd. ..."
"...Mr. Queiroz, I have worked like a beast of burden. ..."