Psalm 149 is an action-packed psalm where singing and dancing contribute to the joy and beauty of celebrating the Lord.

The language of this psalm, especially in the second part is not about killing and cruelty but about how joy and praise in God gives us the power to overcome our lower nature and self-centred desires and urges. (See Heaven and Hell 229)

The psalm twice mentions the word 'saints'. This should not be confused with the traditional Christian view of saints. In New Christian thought, sainthood refers to a state of mind, not a person. A saint is a servant of the Lord – one who lives out his faith in life doing good. For us, we are also saints when we follow the Lord and acknowledge that everything good comes from Him. (See Apocalypse Revealed 586)

The psalm uses the word 'Let' a number of times in its first section. 'Let' carries with it the wish that something be done and brought about. This encapsulates the Lord's wish for us to know and feel His care and reciprocate in serving Him. (See Divine Providence 316)

To 'sing' means to have an affection for what is true and to be glad that we know that the Lord protects our salvation and eternal life. (See Apocalypse Explained 326) To 'sing a new song' (verse 1) is to maintain this joy in repeated new acclamations so that it is forever renewed. Similarly, dancing represents a complete and whole involvement of our joy for the Lord in our life. (See Apocalypse Explained 700)

Verse 4 contains two lovely expressions about the Lord: He takes pleasure in His people, and He will beautify the humble with salvation. These are spiritual superlatives. The first one reminds us that the Lord truly cares about the world; He is not simply an 'operator'. He takes pleasure. Pleasure brings gladness and greater connection between God and us. (See Arcana Celestia 1755) Moreover, those who are truly humble and do not assert their own self-will will be made beautiful by being saved and brought to heaven. (See Arcana Caelestia 5199)

Verse 5 speaks of the saints singing aloud on their beds. Spiritually, a 'bed' stands for our personal beliefs that support us in our life in the same way a bed supports our body in sleep. (See Arcana Caelestia 10360)

The last four verses detail the adventure our spiritual journey entails. When we choose good over evil, we subdue our adversaries in temptation and they have no power over us as we have joy in the Lord. (Arcana Caelestia 5096)

5096. 'Who were bound in the prison house' means which were among falsities. This is clear from the meaning of 'being bound in the prison-house' as being among falsities, dealt with in 4958, 5037, 5038, 5085. Those who are engrossed in falsities, more so those steeped in evils, are called 'the bound" and 'in prison', not because they are held in any physical bonds but because they are not in freedom; for people who are not in freedom are inwardly in bonds. Indeed once they subscribe to falsity they no longer have any freedom to choose or receive what is true; and those who subscribe heavily to it do not have any freedom even to see it, let alone acknowledge it and believe it, because they are quite convinced that what is false is true and what is true is false. That conviction is so powerful in them that it removes all freedom to think anything different, and is so strong that it holds their actual thought in bonds, in prison so to speak. This has been made clear to me from considerable experience among those in the next life who have become quite convinced of falsity by harbouring ideas that serve to prove to it. They are the kind of people who do not entertain any truths at all but turn or drive these away, doing so with a degree of ruthlessness which matches the intensity of their conviction. This is primarily so when such falsity is the product of evil, that is, when evil causes them to be convinced of it. These are the ones who are meant in the Lord's parable in Matthew,

Other seeds fell on the hard path, and the birds came and devoured them. Matthew 13:4.

'Seeds' means Divine truths, 'hard rock' conviction, and 'birds' false assumptions.

[2] People like these are not even aware that they are in bonds or in prison, for they are full of affection for their falsity, loving it because of the evil which produces it. This leads them to think that they are in freedom, since everything they have an affection for or love seems to make them feel free. But those who have not really subscribed to falsity, that is, who have not become convinced of it, entertain truths easily. They see them, choose them, and are full of affection for them, after which they look down on falsities so to speak, and then see how those convinced of falsity have come to be in bonds. Having such freedom they are able in their contemplation and thought to roam so to speak through the whole of heaven in search of countless truths. But nobody can have this freedom except one who is governed by good; for it is by virtue of good that he is in heaven and by virtue of good that truths are seen there.