Psalm 48 is related to the previous two psalms, forming a trilogy of praise which is also seen as being apocalyptic in nature, yet it does have an historical basis. This psalm describes the greatness of God and the glory of His city Jerusalem, which He preserved in a miraculous way. Since He was the King of the world (Psalm 47:7), the city where He chose to put His Name and the site of His Holy Temple deserves honour. He protected Jerusalem from the combined forces of several kingdoms when they came to lay seige against the city (likely referring to the events during the reign of Jehoshaphat, 2 Chronicles 20:1-9, 22-24, 27-30). The enemies' plans against the city were destroyed just as easily as when God sent the east wind to destroy "the ships of Tarshish" (a particular type of ship, but not necessarily from Tarshish, south of Spain;! Kings 22:48; Ezekiel 27:25).
The people of Jerusalem had heard that the Lord of Hosts would protect His city, but now they saw with their own eyes that it was indeed true. Jerusalem's refuge was in God (48:3b, 8; 2 Chronicles 20:14-20). Since it was clear that God had laid claim to Jerusalem, they beleived that God would establish it forever as His eternal city (the earthy city will pass away, but the New Jerusalem will remain forever, Hebrews 11:10,16; 12:22; Revelation 21:2). The psalm began with the exhortation that the Lord be praised "in the city of our God", but after considering His lovingkindness, the worshippers proclaim that He deserves to be praised "to the ends of the earth" (48:9-10). By looking at the sacred places in Jerusalem, the worshippers are reminded of God's goodness and lovingkindness to them and that He would always be their guide, because He was in their midst.
Psalm 49 is directed to all people from all classes, since the message of the Lord is for everyone, and it is the task of His chosen people to proclaim it. The psalmist says that he will reveal some wise words for the purpose of meditating upon the mystery of life (49:4). Since he trusts in the Lord, he has nothing to fear (49:5), but he warns that those who trust in their wealth do have something to fear. No amount of money can ever be used as a ransom for the soul; it cannot rescue anyone from death and decay in the grave (cf. Mark 10:24). The redemption of the soul is costly — something money cannot buy (49:7-9). Only God Himself can redeem a person's soul from the power of the grave (49:15). Our loving God who condescended to become a man, Jesus Christ, paid the price by sacrificing His life to redeem our souls from eternal death (the punishment of sin), that by His shed blood we might have everlasting life (Hebrews 9:12-15; 2 Timothy 1:10; 1 Corinthians 15:20-26, 55; John 5:24).
To encourage the upright who struggle with the age-old question of the prosperity of the wicked (49:16), the psalmist reminds them that wealth cannot be taken with anyone when they die, nor can it buy the wicked salvation: "They shall never see light" (49:19) — the light of life that Jesus gives to those who are His own. All mankind will die and be judged (Hebrews 9:27), yet for the upright there is hope. They "shall have dominion over them [the wicked] in the morning", on that grand and glorious resurrection morning, they shall see the Light when Jesus Christ comes and gives them eternal life with Him (John 5:24-29; 1 John 5:12; 1 Thessalonians 4:14-16).
In Psalm 50, the Lord comes with a manifestation of His glory as the righteous Judge over His covenant people (Exodus 24:3-8). He summons them together, for they are in need of rebuke. They offer him many sacrifices, but the problem is that they have not properly worshiped Him from their heart, and God is interested in the condition of the heart and the motivation behind the sacrifice. All the animals of sacrifice belong to Him, so how can they give Him anything? For the sake of atonement, however, the animals were required. What God desired from His people, as He still does today, was their sincere offering of thanksgiving and their obedience to the covenant stipulations. God wants to see that His people have first offered themselves to Him in total submission and absolute loyalty (50:14; for further study on this topic see Mal. 1:7-8; Isa. 1:11-17; Jer. 7:21-23; Michah 6:6-8; Rom. 6:13; 12:1-2; 1 Cor. 6:20; John 4:23; Heb. 13:15-16). In doing this, the faithful people bring glory to God, and God will be faithful to them and deliver them in times of trouble.
The Lord then addresses those Israelites that know the Law, and even teach it to others, while they themselves do not practice it. They are compromising and hypocritical, and the sin of hypocrisy is detestable to God. For a while the Lord was silent about their behaviour, but He promises to call them to account. He warns them to change their wicked ways, lest they perish and not find salvation. Those who glorify God through praise from a pure heart and live righteously by following His ways will indeed see the salvation of God (50:23).