by Thomas Watson
“Blessed are the pure in heart, for they shall see God.” (v.8)
“Blessed are the poor in spirit, for theirs is the kingdom of heaven.”
“Blessed are those who mourn, for they shall be comforted.”
“Blessed are the meek, for they shall inherit the earth.”
“Blessed are those who hunger and thirst for righteousness, for they shall be satisfied.”
“Blessed are the merciful, for they shall receive mercy.”
“Blessed are the pure in heart, for they shall see God.”
“Blessed are the peacemakers, for they shall be called sons of God.”
“Blessed are those who are persecuted, for theirs is the kingdom of heaven”
Let us put ourselves on TRIAL whether we are pure-hearted or not. Here I shall show the signs of an impure heart; and then, signs of a pure heart.
But how shall we attain to heart-purity?
1. Often look into the Word of God. ‘Now you are clean, through the word’ (John 15:3). ‘Your word is very pure’ (Psalm 119:140). God’s Word is pure, not only for the matter of it—but the effect of it, because it makes us pure. ‘Sanctify them through your truth; your word is truth’ (John 17:17). By looking into this pure crystal—we are changed into the image of it. The Word is both a looking-glass to show us the spots of our souls—and a laver to wash them away! The Word breathes nothing but purity; it enlightens the mind; it consecrates the heart.
2. Go to the bath. There are two baths Christians should wash in.
 The bath of tears. Go into this bath. Peter had sullied and defiled himself with sin and he washed himself with penitential tears. Mary Magdalene, who was an impure sinner, ‘stood at Jesus’ feet weeping’ (Luke 7:38). Mary’s tears washed her heart—as well as Christ’s feet! Oh sinners, let your eyes be a fountain of tears! Weep for those sins which are so many as have passed all arithmetic. This water of contrition is healing and purifying.
 The bath of Christ’s blood. This is that ‘fountain opened for sin and uncleanness’ (Zechariah 13:1). A soul steeped in the brinish tears of repentance and bathed in the blood of Christ is made pure. This is that ‘spiritual washing’. All the legal washings and purifications were but types and emblems representing Christ’s blood. This blood whitens the black soul.
3. Get faith. It is a soul-cleansing grace. ‘Having purified their hearts by faith’ (Acts 15:9). The woman in the gospel who but touched the hem of Christ’s garment was healed. A touch of faith heals. If I believe Christ and all his merits are mine, how can I sin against him? We do not willingly injure those friends who, we believe, love us. Nothing can have a greater force and efficacy upon the heart to make it pure, than faith. Faith will remove mountains, the mountains of pride, lust, envy. Faith and the love of sin are incompatible.
4. Breathe after the Spirit. He is called the Holy Spirit (Ephesians 1:13). He purifies the heart as lightning purifies the air. That we may see what a purifying virtue the Spirit has, he is compared to various things:
 The Spirit is compared to FIRE (Acts 2:3). Fire is of a purifying nature. It refines and cleans metals. It separates the dross from the gold. The Spirit of God in the heart refines and sanctifies it. He burns up the dross of sin.
 The Spirit is compared to WIND. ‘There came a sound from heaven as of a mighty rushing wind, and they were all filled with the Holy Spirit’ (Acts 2:24). The wind purifies the air. When the air by reason of foggy vapors is unwholesome, the wind is a fan to winnow and purify it. Thus when the vapors of sin arise in the heart—vapors of pride and covetousness, earthly vapors—the Spirit of God arises and blows upon the soul and purges away these impure vapors. The spouse in the Canticles prays for a gale of the Spirit, that she might be made pure (4:16).
 The Spirit is compared to WATER. ‘He who believes on me, out of his belly shall flow rivers of living water; but this spoke he of the Spirit’ (John 7:38, 39). The Spirit is like water, not only to make the soul fruitful, for it causes the desert to blossom as the rose (Isaiah 32:15; 35:1)—but the Spirit is like water to purify. Whereas, before, the heart of a sinner was unclean and whatever he touched had a tincture of impurity (Numbers 19:22), when once the Spirit comes into the heart, with his continual showers, he washes off the filthiness of it, making it pure and fit for God to dwell in.
5. Take heed of close converse and fellowship with the wicked. One vain mind makes another vain. One hard heart makes another. The stone in the body is not infectious—but the stone in the heart is. One profane person poisons another. Beware of the society of the wicked.
Some may object: But what hurt is in this? Did not Jesus converse with sinners? (Luke 5:29).
 There was a necessity for that. If Jesus had not come among sinners, how could any have been saved? He went among sinners—but not to join with them in their sins. He was not a companion of sinners—but a physician of sinners.
 Though Christ did converse with sinners, he could not be polluted with their sin. His divine nature was a sufficient antidote to preserve him from infection. Christ could be no more defiled with their sin—than the sun is defiled by shining on a dunghill. Sin could no more stick on Christ—than a burr on a crystal. The soil of his heart was so pure—that no viper of sin could breed there. But the case is altered with us. We have a storehouse of corruption within, and the least thing will increase this storehouse. Therefore it is dangerous mingling ourselves among the wicked. If we would be pure in heart—let us shun their society. He who would preserve his garment clean, avoids the dirt. The wicked are as the mire (Isaiah 57:20). The fresh waters running among the salt waters, taste brackish.
6. If you would be pure, walk with those who are pure. As the communion of the saints is in our Creed, so it should be in our company. ‘He who walks with the wise, shall be wise’ (Proverbs 13:20), and he who walks with the pure, shall be pure. The saints are like a bed of spices. By intermixing ourselves with them we shall partake of their savouriness. Association begets assimilation. Sometimes God blesses godly society, to the conversion of others.
7. Wait at the posts of wisdom’s doors. Reverence the Word preached. The Word of God sucked in by faith (Hebrews 4:2) transforms the heart into the likeness of it (Romans 6:17). The Word is a holy seed (James 1:18), which being cast into the heart makes it partake of the divine nature (2 Peter 1:4).
8. Pray for heart purity. Job propounds the question, ‘Who can bring a clean thing out of an unclean?’ (Job 14:4; 15:14). God can do it. Out of an impure heart—he can produce grace. Pray that prayer of David, ‘Create in me a clean heart, O God’ (Psalm 51:10). Most men pray more for full purses, than pure hearts. We should pray for heart-purity fervently. It is a matter we are most nearly concerned in. ‘Without holiness no man shall see the Lord’ (Hebrews 12:14). Our prayer must be with sighs and groans (Romans 8:23-26). There must not only be elocution but affection. Jacob wrestled in prayer (Genesis 32:24). Hannah poured out her soul (1 Samuel 1:15). We often pray so coldly (our petitions even freezing between our lips), as if we would teach God to deny our prayers. We pray as if we did not care whether God heard us or not!
Oh Christian, be earnest with God for a pure heart! Lay your heart before the Lord and say, “Lord, You who have given me a heart, give me a pure heart. My heart is good for nothing as it is. It defiles everything it touches. Lord, I am not fit to live with this heart—for I cannot honor you; nor fit to die with it—for I cannot see you. Oh purge me with hyssop. Let Christ’s blood be sprinkled upon me. Let the Holy Spirit descend upon me. ‘Create in me a clean heart, O God’. You who bid me to give you my heart—Lord, make my heart pure and you shall have it!”