Three times in the first half of the sixth chapter of the Gospel of Matthew these words of the Savior are given. Let us note that He says this about almsgiving, prayer, and fasting. There is a small book by Vladimir Solovyov, "The Spiritual Foundations of Life," in which he writes about prayer, almsgiving, and fasting as the main components of a person's righteous life. Indeed, each person's "position" in the universe is determined by his relations along three "coordinate axes" - connection with God, connection with other people, and connection with nature. Prayer, almsgiving, and fasting are expressions of right relations along these "axes."
Thus Jesus' words refer thereby to the whole fullness of human life. He says that this life is carried out not so much visibly as "in secret," not so much in actions as in the intentions of the heart, not so much in deeds as in relationships. And accordingly, the visible reward of this world is not important for us, because it proves to be transient along with this world, but the reward from the invisible God is important, because it is eternal life.