The answer
The pure heart is the inner eye of the spirit that sees what cannot be seen. The word “purity” in Greek refers to washing and purification, as when one removes dirt from clothes. It can also mean purifying what is good by removing from it what is bad; like separating wheat from chaff, or purging an army of cowards. And it can also denote a pure, unadulterated substance, such as milk with no additives. Likewise, the heart that at all times bows at the feet of our Lord Jesus Christ is at all times washed clean by the Holy Blood and purged of every impurity, and guarded from domination by any wicked desire by the Holy Spirit Himself who permeated it through the sacraments of Baptism and Confirmation. Thus the heart becomes clear and pure, together with all its desires, feelings, and motives, seeking nothing from anything but God alone; and sees Him by faith through the Holy Spirit dwelling in it.
St. Augustine says:
“Let us be purifying our hearts by faith, that we may be prepared for that ineffable and, so to speak, invisible vision.”1265
“Let him strive by continence to purify that which he may lift up to God.”1266
“This is the end of our love; an end whereby we are perfected, and not consumed … when we come to the vision of God, we shall require no more. For what need he seek for, with whom God is present? … How often already has he enumerated the blessed, and the causes of their blessedness, and their works and recompenses, their merits and rewards! But nowhere [else] has it been said, ‘They shall see God’ … When we come to the ‘pure in heart,’ there is the vision of God promised. And not without good cause; for there, in the heart, are the eyes, by which God is seen. Speaking of these eyes, the Apostle Paul says, ‘The eyes of your heart being enlightened’ (Eph. 1:8). At present then these eyes are enlightened, as is suitable to their infirmity, by faith; hereafter as shall be suited to their strength, they shall be enlightened by sight. ‘For as long as we are in the body we are absent from the Lord; for we walk by faith, not by sight’ (2 Cor. 5:6–7). Now as long as we are in this state of faith, what is said of us? ‘We see now through a glass darkly; but then face to face’ (1 Cor. 13:12).”1267
The scholar Origen says, “Whoever has a pure heart will see God (cf. Matt. 5:8). Whoever does not, will not see what the other beholds. I think we should understand something similar of Christ, too, when he was seen in the body. Not everyone who laid eyes on him was able to see him. They saw his body, but, insofar as he was Christ, they could not see him. But his disciples saw him and beheld the greatness of his divinity.”1268
St. Clement of Alexandria says, “For what rational cause remains any more to the man who has gained ‘the light inaccessible’ (1 Tim. 6:16) for reverting to the good things of the world?”1269
And St. John Chrysostom says, “Now He here calls ‘pure,’ either those who have attained unto all virtue, and are not conscious to themselves of any evil; or those who live in temperance. For there is nothing which we need so much in order to see God, as this last virtue. Therefore Paul also said, ‘Follow peace with all men, and holiness, without which no man shall see the Lord’ (Heb. 12:14).”1270
Fr. Tadros Yacoub Malaty
Notes
1264 See Fr. Tadros Yacoub Malaty, The Book of Matthew: A Patristic Commentary (undated): Chapter 5.
1265 St. Augustine of Hippo, Lectures or Tractates on the Gospel According to St. John 53.12 (NPNF I/7:295).
1266 St. Augustine of Hippo, Lectures or Tractates on the Gospel According to St. John 1.7 (NPNF I/7:9).
1267 St. Augustine of Hippo, Sermons on Selected Lessons of the New Testament 3.6 (NPNF I/6:267) amended.
1268 Origen of Alexandria, Homilies in Luke 3.3–4 (FOTC 94:15).
1269 St. Clement of Alexandria, The Stromata, or Miscellanies 6.9 (ANF 2:497).
1270 St. John Chrysostom, Homilies on Matthew 15.6 (NPNF I/10:91) amended.