[The book of Psalms] is, as Calvin says, “an anatomy of all the parts of the soul.” It is a guide to piety for the believer. In particular the book of Psalms provides guidance for the Christian in four areas: meditation, expostulation, prayer, and song.
The art of Christian meditation is in our age largely a lost art, though our Puritan and Reformed forefathers wrote dozens of treatises on the subject. The term meditation has been appropriated by the practitioners of Eastern and New Age religions. Insofar as meditation has come into the evangelical church it has often come in under a baptizing of these New Age ideas. Meditation, as understood and practiced by New Age religions, is an emptying of the mind. It is an attempt to achieve a sort of mindless spiritual condition in which the one meditating becomes open to “spiritual forces,” having been emptied, as it were, of himself and thus ostensibly open to the presence of God. The book of Psalms, on the other hand, teaches the reader what true biblical meditation is. Consider Psalm 1:2: “His delight is in the law of the Lord, and on his law he meditates day and night.” In understanding the point this verse makes, it first must be understood that law here is not limited to the legal sections of the Old Testament. The word translated law is torah, and it means not just legal statements but “every word that comes from the mouth of the LORD” (Deuteronomy 8:3). Thus, the practice of Chrisitian meditation is an intellectual, spiritual exercise in which the believer reflects on and considers the Word of God, seeking first to understand it and second to apply it to himself. The word translated meditate has the idea of “mutter,” hence the idea of repeating, chewing over what has been read. Psalm 119 is an example for the believer of a meditation on the law of God. Virtually every verse in the psalm refers to torah, or some synonym as verse by verse the psalmist seeks to understand the meaning of God’s Word for his own life. A number of the psalms are particularly useful as guides to meditation, among them Psalms 1, 34, 37, 49, 111, 112, and 119.
–from “The Psalms” by Benjamin Shaw,
Tabletalk Magazine, February 2007, Volume 31, Number 2
Dr. Benjamin Shaw is professor of Hebrew and Old Testament at Greenville Presbyterian Theological Seminary in Greenville, South Carolina.
The Misadventures of Captain Headknowledge 
aaaah
what were you thinking?
One can know another by understanding the reason they do what they do or how they think.
It is not true the other way around.
For instance, God knows us. That is settled among Believers. Not among athiests though.
But, we cannot know God unless God knows us!
How does God know us, or rather, help us know ourselves as He knows us?
As you have taught hereon, by meditation, meditating on God and His Word day and night brings knowledge of God and ourselves.
2Ti 2:19 But God’s firm foundation stands, bearing this seal: “The Lord knows those who are his,” and, “Let everyone who names the name of the Lord depart from iniquity.”
And the Apostle said somewhere else:
[it’s a long quote, but meditate on it and you will HAVE PEACE]
Rom 7:6 But now we are released from the law, having died to that which held us captive, so that we serve not under the old written code but in the new life of the Spirit.
Rom 7:7 What then shall we say? That the law is sin? By no means! Yet if it had not been for the law, I would not have known sin. I would not have known what it is to covet if the law had not said, “You shall not covet.”
Rom 7:8 But sin, seizing an opportunity through the commandment, produced in me all kinds of covetousness. Apart from the law, sin lies dead.
Rom 7:9 I was once alive apart from the law, but when the commandment came, sin came alive and I died.
Rom 7:10 The very commandment that promised life proved to be death to me.
Rom 7:11 For sin, seizing an opportunity through the commandment, deceived me and through it killed me.
Rom 7:12 So the law is holy, and the commandment is holy and righteous and good.
Rom 7:13 Did that which is good, then, bring death to me? By no means! It was sin, producing death in me through what is good, in order that sin might be shown to be sin, and through the commandment might become sinful beyond measure.
Rom 7:14 For we know that the law is spiritual, but I am of the flesh, sold under sin.
Rom 7:15 I do not understand my own actions. For I do not do what I want, but I do the very thing I hate.
Rom 7:16 Now if I do what I do not want, I agree with the law, that it is good.
Rom 7:17 So now it is no longer I who do it, but sin that dwells within me.
Rom 7:18 For I know that nothing good dwells in me, that is, in my flesh. For I have the desire to do what is right, but not the ability to carry it out.
Rom 7:19 For I do not do the good I want, but the evil I do not want is what I keep on doing.
Rom 7:20 Now if I do what I do not want, it is no longer I who do it, but sin that dwells within me.
Rom 7:21 So I find it to be a law that when I want to do right, evil lies close at hand.
Rom 7:22 For I delight in the law of God, in my inner being,
Rom 7:23 but I see in my members another law waging war against the law of my mind and making me captive to the law of sin that dwells in my members.
Rom 7:24 Wretched man that I am! Who will deliver me from this body of death?
Rom 7:25 Thanks be to God through Jesus Christ our Lord! So then, I myself serve the law of God with my mind, but with my flesh I serve the law of sin.