In this painting, the red and green are complementary colors on opposite sides of the painting. "When placed next to each other, [complementary colors] create the strongest contrast..." according to Wikipedia. I think of these colors as complete opposites, fighting with each other. The introduction of the yellow between them is intended to communicate a dissimilar concept entirely; something that unifies or consolidates the whole. The 'peace' in the painting is brought about by moving the focus from the opposing points to a clear, new position.
Another version of the verse looks like this: Matthew 5:9 (AMP) Blessed (enjoying enviable happiness, spiritually prosperous— with life-joy and satisfaction in God’s favor and salvation, regardless of their outward conditions) are the makers and maintainers of peace, for they shall be called the sons of God!
6" x 6" acrylic on 1.5" deep canvas, sides painted black