Contemplation of dhātus: One way of Vipassanā meditation

If poor teaching and training for an energetic person, life in suffering (AN 1.324)

If good teaching and training for a lazy person, life in suffering (AN 1.325)

If poor teaching and training for a lazy person, life in happiness (AN 1.326)

If good teaching and training for an energetic person, life in happiness (AN 1.327)

Dhātu contemplation, the comprehension of everything in terms of four primaries and one secondary

Then, no clinging to anything, and hence no friction and resistance of ignorance

Less exhaustion of the resources, lesser need of power

More in less with efficiency, and when the coupling with few wishes, even much more

So, a method of transformation from sluggishness or lethargy to full of energy

Moreover, intensity of happiness even above higher realms and not suffering like lower realms like hell

Not only higher but highest formless realm

The realm of 'neither perception, nor non-perception'

Because no clinging or no perception, and only dhātus

Also, not non-perception because perception of dhātus