And by the sky containing constellations,

And by the promised day,

And by a witness and what is witnessed,

Cursed be the companions of the trench,

The meaning is that recompense for deeds is a truth.

When the sky splits apart,

And obeys its Lord, as it is obliged to do,

And when the earth is extended,

And casts out what is within it and becomes empty,

And obeys its Lord, as it is obliged to do,

O mankind, indeed you are toiling toward your Lord...

the verse.

The meaning is that the reckoning and recompense are certain to occur.

Shifting from Address to Absence:

And sometimes they shift the style of speech so that the context, for example, demands direct address, yet they use the third-person absent form for considered rhetorical reasons.

Among its examples is His statement - the Most High -:

"Until, when you are in ships and they sail with them by a favorable wind..."

Shifting from Informative Statement to Performative Expression:

And sometimes they bring a sentence of direct command or request in place of an informative statement.

And among its examples is His statement - the Most High -:

"So walk among its regions"

meaning: so that you may walk.

"If you are believers"

meaning: your faith necessitates this.