“And as St. Augustine reminds us in the following reflections, sand is thrown in the eyes of the heart not only by a multiplicity of images, not only by association of ideas, but also by the refusal to serve one’s neighbor in practical ways. To be too busy filling the coffers prevents one from emptying one’s heart so as to make it attentive to the ‘interior Master’. For ‘where your treasure is,’ says Jesus, ‘there will your heart be also.’
To purify yourself, have faith. You would like to see God. That desire is good, it is noble, and I challenge you to make trial of it. You would like to see him? ‘Blessed are the pure in heart, for they shall see God.’ (Matthew 5.8). Think first of all about purifying your heart…You believe that God is evident to the eyes like a light…But if your eyes were clogged with sand, would you not have to wash them out before you could see the light?
Your heart is defiled also. And avarice spreads its murkiness there…Do you not realize that by hoarding in this way you are covering your heart with mud? How then will you see him whom you desire?
You say to me, ‘Show me your God.’…
I answer you, ‘Take a look at your heart. Everything you see in it that might sadden God, remove. God wants to come to you. Listen to Christ your Lord: “My Father and I will come to him and make our home with him” (John 14.23). That is God’s promise. If I were to tell you I was coming to stay with you, you would clean your house. Now it is God who wants to come into your heart. Do you not hasten to purify it? How could he dwell with avarice? God has commanded you to clothe the naked. But avarice induces you to strip the one who is clothed…I am looking at your heart. What do you have in it? Have you filled your coffers but thrown away your conscience?…Purify your heart.’ (Augustine of Hippo)”
(quoted in Roots of Christian Mysticism, p. 166-167)