Although not as highly publicized as many other more famous paintings, the Holy Trinity by Masaccio might just be the most important painting in Florence, and is certainly one of the most important of all time. The reason is that it is the first painting ever, in the entire history of art, to apply a technology known as linear or single-point perspective. Suddenly, painting could no longer only look 3-dimensional, it now was 3-dimensional!!! This lecture will explore the mathematical principles behind the great painting, as well as how for the first time science and theology synergized in Renaissance art.