Bible Commentary
1 A glimpse at the open sky with the naked eye is sufficient to impress upon the beholder a sense of the glory of God. Wisdom, power, skill and benevolence are the things that constitute God's glory. By their splendour and order the heavens disprove evolution. They are not the work of chance, but the creation of God. Their beauty and arrangement argue God's existence.²
2 As if one day took up the story where the other left it, and each night passed over the wondrous tale to the next. The original has in it the thought of pouring out or welling over, with speech; as though days and nights were but as a fountain flowing evermore with Jehovah's praise. The witnesses above cannot be slain or silenced; from their elevated seats they constantly preach the knowledge of God, unawed and unbiased by the judgment of men.²
3 Despite the fact that the heavens have a language of their own, their voice is inaudible (see vs, 1, 2), it does not speak to the ear, but is pictorial and directed to the eye and heart.²
4 Although the heavenly bodies move in solemn silence, they speak by their significant actions and operations. By their line is probably meant the measure of their domain which, together with their testimony, has gone out to the utmost end of the habitable earth. In the heavens the sun encamps, and marches like a mighty monarch on his glorious way. As the royal pavilion stood in the centre of the host, so the sun in his place appears like a king in the midst of attendant stars.²
5 A bridegroom comes forth sumptuously apparelled, his face beaming with a joy which he imparts to all around. The sun comes out of his chamber (beneath the horizon), where he spends the night, and bursts forth at dawn, lighting up his glorious "tabernacle". As a champion girt for running cheerfully addresses himself to the race, so does the sun speed onward with matchless regularity and unwearying swiftness in his appointed orbit. It is but mere play to him; there are no signs of effort, flagging, or exhaustion.²
6 He bears his light to the boundaries of the solar heavens, traversing the zodiac with steady motion, denying his light to none who dwell within his range. Above, beneath, around, the heat of the sun exercises an influence. Although many things may be concealed from the light of the sun, its heat (the vital force from which the earth gets its life and energy) penetrates everywhere.²
7 At this point David turns from his contemplation of nature, revealing in its grandeur, permanence, and purpose the glory of God, to the contemplation of the even clearer revelation of God in the law. As the sun illuminates and gives life to the material earth, so the law lights and energises the spiritual world. The law refreshes and invigorates. The revelation of God is God's witness or testimony, because it is His own affirmation concerning His nature, attributes, and consequent commands.² The testimony of the Lord is faithful, lasting and firmly established. The childlike spirit is the first essential to gaining wisdom. Humble, candid, teachable minds receive the word, and are made wise unto salvation.²
8 God's precepts and decrees are founded in righteousness. As a physician gives the right medicine, and a counsellor the right advice, so does the Book of God. Mark the progress; he who was converted was next made wise and is now made happy; that truth which makes the heart right then gives joy to the right heart. The commandment of the Lord is not defiled by any mixture of error nor polluted by stain of sin. As the sun gives light to the world, so God's commandments light man's pathway in his search for truth.²
9 The fear of the Lord is the "instruction of wisdom" (Prov. 15:33). The man who fears God will also respect and observe His precepts. He will display a holy fear or reverence in service and worship. The worship of God is free from the defiling rites that characterised the Canaanite religions. The revealed will of God is constant and unchangeable. The judicial decisions of Jehovah, as revealed in the law, or illustrated in the history of his providence, are truth itself, and commend themselves to every truthful mind; not only is their power invincible, but their justice is unimpeachable.²
10 Gold is regarded as an article of great value among men, but spiritual riches gained through following God's precepts are far superior to material wealth. Honey is one of the sweetest of all natural substances and a delight to the taste. To the Hebrew it was a symbol of all that was pleasant to the palate. Even sweeter to the soul are God's commandments. "O taste and see that the Lord is good" (Ps. 34:8). One could become sated with honey, but never with the joyful results of obedience to the will of God. To the psalmist God's law was not burdensome, it was not a yoke.²
11 We are warned by the Word both of our duty, our danger, and our remedy. On the sea of life there would be many more wrecks, if it were not for the divine storm signals, which give to the watchful a timely warning. Saints may be losers for a time, but they shall be glorious gainers in the long run, and even now a quiet conscience is in itself no slender reward for obedience. However, the main reward is yet to come, at the end of life when the work is done. Our light affliction, which is but for a moment, is not worthy to be compared with the glory which shall be revealed in us (Rom. 8:18).²
12 In view of the far-reaching demands of God's law, we are likely to make many mistakes of which we are unaware. These are the secret (literally, "hidden") faults of the second half of the parallelism. They may be hidden both from the one who sins and from the world. The psalmist prays for deliverance from "secret faults" (Ps. 19:12), "presumptious sins" (v. 13), and sins of word and thought (v. 14).²
13 Presumptuous sins are the sins committed when we know that we are doing wrong. They are contrasted with "errors" and "secret faults". It is remarkable that though an atonement was provided under the Jewish law for every kind of sin, there was this one exception: "But the soul that sinneth presumptuously shall have no atonement; it shall be cut off from the midst of the people." And now under the Christian dispensation, through the sacrifice of our blessed Lord there is a great and precious atonement for presumptuous sins, whereby sinners who have erred in this manner are made clean. However the presumptuous sinner who dies without pardon, must expect to receive a double portion of the wrath of God. David is assured that, providing the presumptuous sins have not dominion over him, then he will be upright and innocent of the unpardonable sin.²
14 Having prayed that God would keep him from sinful actions, the psalmist now prays that God would govern, and sanctify his words and thoughts: and this was necessary to preserve him from presumptuous sins, which have their first rise in the thoughts. The psalmist's prayer is directed to God who is his strength and Redeemer, and who is able to deliver him from the power and guilt of sin.²
 

References and notes
1.  King James Authorized Version
2.  SDA Bible Commentary  Vol 3 pgs. 675-678
3.  Charles H. Spurgeon, "The Treasury of David" - http://bible.crosswalk.com/Commentaries
4.  Walking Thru the Bible: Psalms - http://fly.hiwaay.net/~wgann/walk_ot/psalms.htm
5.  Bible Study - King David - www.execulink.com/~wblank/20000130.htm
6.  Easton Bible Dictionary - www.hyperdictionary.com/dictionary/David
7.  Scientific Facts In The Bible By Living Water Publications - www.inplainsite.org/html/scientific_facts_in_the_bible.html