@Overpressure I conjecture your cynical reaction to songs that mention heaven might involve what i think i remember as your well defended rationalist/materialist stance? Well i agree that promises of heaven are a cop out, but what if
1) Spinoza was right and there is really ultimately only 1 "substance" and we are all a part of this.
1a) Time is an aspect of that "substance"
2) The multiverse is conscious in a way you have yet to sense or measure.
Relevant to this thread it then follows that sadness is eternal. (Which is perhaps why
@Haj01 tries real hard to stay happy.)
1) and 1a) are very easily defendable in our mundane language and 4 dimensions.
Statement 2) is something some people recieve as a gift in part or in whole. When they get just a part gifted they found world religions.
Of course it could all be just a lightshow in the brain, but there are pathways in the brain you can access that for a moment show you a flash of the whole fucking thing and it is quite sad and quite happy and everything is alive, dying.
Human music I believe is a particularly important creation that helps structure everything.
Still for pure sadness I cant top Marie yet, but Buffy St. Marie comes close with this the saddest christmas song...