There's quite a decent diversity of backgrounds here it seems, especially adding Joe Chi Minh's and other contributions above. If I have by chance included one or more that some disrespect, then I have succeeded more than I reasonably hoped for!

“Words are just words, and without heart they have no meaning.”
--Chinese Proverb

“Does this path have a heart? If it does, the path is good; if it doesn't, it is of no use. Both paths lead nowhere; but one has a heart, the other doesn't. One makes for a joyful journey; as long as you follow it, you are one with it. The other will make you curse your life. One makes you strong; the other weakens you.”
–Carlos Castaneda, author of “The Teachings of Don Juan” concerning Mesoamerican shamanism

“We know the truth, not only by the reason, but also by the heart.”

--Blaise Pascal – French 17th Century mathematician, physicist, philosopher, inventor, theologian, prose stylist and polemicist, (1) first achieving fame at the age of 16 with a contribution to the projective geometry of a cone, including “Pascal’s Theorem” (2) the original development of probability theory, the basis of statistics, together with Fermat (3) work on barometric air pressure varying by altitude above sea level (4) credit given by Leibniz to Blaise Pascal’s method for infinitesimal analysis as the inspiration for Leibniz’s development of calculus.

“For where your treasure is, there your heart will be also.”
--Matthew 6: 21 ESV

“That which is spoken from the heart is heard by the heart.”
–Jewish Saying

“Man looks at the outward appearance, but the Lord looks at the heart.”
--1 Samuel 16: 76

“The heart of the matter is a matter of heart.”
--Rick Warren “The Purpose-Driven Life” (modern evangelical work)