The Dhammapada 371 :"
Meditate, o bhikkhu and be not heedless."
The atthakatha(Commentary) says "o bhikkhus meditate by the two kinds of meditative absorptions" And the tika notes that this is twofold in "the sense of meditative absorption that arises depending on an object and meditative absorption that arises dependent on characteristics" The tika later explains this by saying that the first is (p506 note 6 of carter and palihawadana) "
"the eight attainments (jhanas) to be obtained by training the mind in concentrating on one of the thirty eight objects such as kasina [or metta, or Buddha or Dhamma or breath etc] and the second means 'insight wisdom, path and fruit'..to be obtained by reflecting on the three characteristics'
Now when it says 'reflecting' this includes direct insight into the actual characteristics and conditions of the present moment(patipatti) right up to the vipassana nanas and magga and phala(pativedha). The Dhammapada pradipaya (see p457 of carter) says "
"to consider the coming into being of rupa on account of ignorance, craving, kammaand nutrition, and also to see the mere characteristics of its instantaneous coming into being, without looking for causative aspect; thus one should consider the rise of rupa in five ways. Likewise to consider the rise of
the other 4 khandas in the same way...Thus the rise of the pancakkhanda (five aggregates )is seen in 25 ways. To see that the rise of the khandas is stopped by abolishing the causes:ignorance, craving, kamma and nutrition..in this way the cessation of the agregates should be seen