I came across all three quotes below in the Opening the Word study program for the 13th Sunday in Ordinary Time, Year A on Formed.
“Direct your thoughts to… bearing the crosses, little or great, that you will find there. Believe me, this is the most important and least understood point to the spiritual life.”
—St. Francis de Sales
(I couldn’t find the original source of this quote.)
“Sacrifice is always the raw material God uses to convert man to love.”
—Fr. Brian Bransfield, from The Human Person: According to John Paul II
“Man… finds himself only by making a sincere gift of himself to others.”
—Gaudium et Spes (24)