Psalm 104: The Creation Psalm

The 104th Psalm has long been known as the "Creation Psalm." This psalm presents a poem about the creation of the world, and it contains several key passages that contains clues about key topics related to the creation, such as the flood, death before the fall of man, and the age of the earth.
First, let us establish a basis for the fundamentalist, young earth view of this passage. The Liberty Bible Commentary, produced by Jerry Falwell, states that the theme of this Psalm is "A poet's version of the creation chapters of Genesis." For the remainder of this article, the Liberty Bible Commentary will be referred to as the LBC.1
Second, consider the venerable commentary by Matthew Henry. Though no theme is given, it is clear that creation is the main theme. Hereafter Matthew Henry's Commentary will be referred to as MH. We will follow the standard divisions set by MH.2
Verses 1-4, The Splendour of His Majesty in the Upper World
Bless the LORD, O my soul! O LORD my God, thou art very great! Thou art clothed with honor and majesty, who coverest thyself with light as with a garment, who hast stretched out the heavens like a tent, who hast laid the beams of thy chambers on the waters, who makest the clouds thy chariot, who ridest on the wings of the wind, who makest the winds thy messengers, fire and flame thy ministers.
The first four verses do not present anything significant for an old earth/young earth debate. It affirms that the topic is God, and his great majesty at the beginning of creation.
Verses 5-9, The Creation of the Sea and the Dry Land
Thou didst set the earth on its foundations, so that it should never be shaken. Thou didst cover it with the deep as with a garment; the waters stood above the mountains. At thy rebuke they fled; at the sound of thy thunder they took to flight. The mountains rose, the valleys sank down to the place which thou didst appoint for them. Thou didst set a bound which they should not pass, so that they might not again cover the earth.
This portion of scripture is the most important for the creation debate. That it is referring to Genesis Chapter One is agreed upon by MH and LBC. Verses 5 and 6 detail the waters which covered the globe (Genesis 1:2, 9). LBC states for verse 7, "the waters shifted into the places established by God (Gen. 1:9)." MH also refers back to Gen 1:9.
Some young earth creationists have referred to this passage as proof of the Genesis Flood. Mr. Kent Hovind claims that "The large mountains, as we have them today, did not exist until after the Flood when "the mountains arose and the valleys sank down" (Ps. 104:5-9, Gen. 8:3-8)."3 It is clear however that this passage refers to Genesis 1, not to the post-flood world. Ken Ham, in Chapter 12 of his Answers Book, uses this argument to explain away the problem of the waters of the flood. However, it is an invalid argument when considering that Psalm 104 refers to the creation, and not the Flood.4,5 And finally, geologist Andrew Snelling uses it in his article on cave formation, with the same false premise.6
The most interesting conclusion we can make with this passage is that it invalidates the possibility of a worldwide flood. God sets a boundary that the waters may not pass over (verse 9). If you believe the Flood was global, then you must conclude that either God was unable to maintain this boundary, or that He went back on His word. MH states that "the waters are forbidden to pass over the limits set them; they may not, and therefore they do not, turn again to cover the earth."7
LBC states "Except for the Great Deluge, which for the purpose of his poetry is excluded by the poet, God had set a bound for the waters that they may not pass over."8 LBC accepts that the passage is for Genesis 1, but argues for an exception. There is no evidence, nor compelling reason, to suspect that the poet did not mean what he said. If he (God) had intended to exclude the Flood, He would not have made this statement. Either God lied by flooding the world, or it was a local flood event. If you believe in a young earth with a global flood, you must believe that God lied in Psalm 104:9.
Verses 10-18, The Provision He makes for the maintenance of all the creatures according to their nature
Thou makest springs gush forth in the valleys; they flow between the hills, they give drink to every beast of the field; the wild asses quench their thirst. By them the birds of the air have their habitation; they sing among the branches. From thy lofty abode thou waterest the mountains; the earth is satisfied with the fruit of thy work. Thou dost cause the grass to grow for the cattle, and plants for man to cultivate, that he may bring forth food from the earth, and wine to gladden the heart of man, oil to make his face shine, and bread to strengthen man's heart. The trees of the LORD are watered abundantly, the cedars of Lebanon which he planted. In them the birds build their nests; the stork has her home in the fir trees. The high mountains are for the wild goats; the rocks are a refuge for the badgers.
God provides for his creatures, creating grass for cattle, plants for man, and wine for man. Both old and young earth have no problems with this passage.
Verses 19-24, The Regular Course of the Sun and Moon
Thou hast made the moon to mark the seasons; the sun knows its time for setting. Thou makest darkness, and it is night, when all the beasts of the forest creep forth. The young lions roar for their prey, seeking their food from God. When the sun rises, they get them away and lie down in their dens. Man goes forth to his work and to his labor until the evening. O LORD, how manifold are thy works! In wisdom hast thou made them all; the earth is full of thy creatures.
It is interesting that this entire Chapter is referring to Genesis 1, yet we have in verse 21 young lions seeking their prey. Young earth theory does not believe in death, even animal death before the fall, yet here we have a clear case of carnivorous activity in Genesis 1, before the fall of man. LBC and MH make no arguments against this carnivorous activity. But wait...there's even clearer evidence of this a few verses later.
Verses 25-26, The Furniture of the Sea
Yonder is the sea, great and wide, which teems with things innumerable, living things both small and great. There go the ships, and Leviathan which thou didst form to sport in it.

Leviathan is referring to whales according to LBC. MH makes no mention of Leviathan.
Verses 27-30, God's Sovereignty over the Creatures
These all look to thee, to give them their food in due season. When thou givest to them, they gather it up; when thou openest thy hand, they are filled with good things. When thou hidest thy face, they are dismayed; when thou takest away their breath, they die and return to their dust. When thou sendest forth thy Spirit, they are created; and thou renewest the face of the ground.

Here we depart somewhat from MH's divisions. Here we have an even clearer case for carnivorous activity. It is clear that God provides food for His creatures. It is also clear that His creatures die. But most compelling is verse 30, where God creates them, and renews the ground. God's creative acts ended at the end of Day 6, with the creation of man. Thus, here we have God creating animals AFTER previous animals had died and returned to dust! The renewing of the ground is a clear indication of the renewing nature of God's creation, i.e. the food chain. As animals die, they decay and feed the plants, which in turn are eaten by plant-eating animals, who in turn are eaten by meat-eating animals, and the process starts all over. God's self-renewing creation is perfect for a system which maintains itself, and is indeed "very good" as God states in Genesis 1:31.
LBC does not address this conflict with their own young earth theory. They denounce evolution, but fail to address this death before the fall.
Verses 31-35, Closing
May the glory of the LORD endure for ever, may the LORD rejoice in his works, who looks on the earth and it trembles, who touches the mountains and they smoke! I will sing to the LORD as long as I live; I will sing praise to my God while I have being. May my meditation be pleasing to him, for I rejoice in the LORD. Let sinners be consumed from the earth, and let the wicked be no more! Bless the LORD, O my soul! Praise the LORD!

The closing presents no information for the age debate.
Conclusion
It is clear from this passage that Noah's Flood had to be local, and that there was animal death prior to the fall of man, thus contradicting the young-earth interpretation of the creation. This passage fits well with an old-earth interpretation, and provides no challenges against old earth belief.
For Further Reading:
Death Before Sin, from Genesiscreation.org (http://www.genesiscreation.org/deathbeforesin.html)
1 Liberty Bible Commentary: Old Testament, Thomas Nelson Publishers, 1982.
2 Matthew Henry's Commentary In One Volume, Zondervan Publishing House, 1961.
3 Points to Ponder about the Flood, from the website drdino.com (http://www.drdino.com/QandA/index.jsp?varFolder=Flood&varPage=PointstoPonderAbouttheFlood.jsp).
4 The Answers Book, MasterBooks, pp. 174-175.
5 A review of Chapter 12 of The Answers Book, on the Answers In Creation website
6 Limestone Caves, Answers in Genesis website (http://www.answersingenesis.org/creation/v9/i4/caves.asp)
7 Matthew Henry, page 689.
8 Liberty Bible Commentary, page 1120.