Chapter 129

This psalm is basically a "curse" pronounced on the enemies of the nation of Israel.  vs 5 seems to be the central theme:

5 May all who hate Zion be put to shame and turned backward! [Psa 129:5 ESV]

Does this still apply to them, though their covenant is abrogated?  Surely in some measure it does. 

2021 - The last 3 verses are talk about grass.  The grass used to make roofs on the house.  My guess is that this grass is inferior and not suitable for hay, not nutritious enough maybe for livestock.  It is so useless that it's only used to make roofs.  I don't know this is the case of course, but the harvesters don't fill their hands with it and the binders don't prep it for storage.  Surely these ideas don't apply to useful grains.  MSB says it was grass with shallow roots, which quickly dies with the first heat, depicts the wicked.  Hmm.  Yes, that makes sense.  But it looks to me like there's more to it than that.