Phowa

Phowa is a very important teaching particularly for lower level practitioners. Those who don't have time to practice for their entire lives still have a chance to attain enlightenment through these instructions.

It is stated in the Words of My Perfect Teacher:

This technique is essential for practitioners who have not attained stability on the path, or who have committed numerous harmful actions. For anyone holding these special instructions, however serious his or her wrong actions, the gates of the lower realms are closed. Even those who have committed a crime with immediate retribution, and so would otherwise fall straight downwards, will definitely not be reborn in the lower realms if they use this teaching.

The tantras say:

You might have killed a brahmin every day,
Or committed the five acts with immediate retribution,
But you will still be liberated by this path.
None of those crimes will defile you.
Whoever practices this transference,
Concentrating on the opening above the other nine,
Will not be defiled by his negative acts,
And will be reborn in a pure Buddhafield.

The Buddha Vajradhara said:

You might have killed a brahmin every day,
Or committed the five acts with immediate retribution,
But once you encounter these instructions,
You will, beyond any doubt, be liberated.

And the great Padmasambhava says:

Everyone knows about Buddhahood through meditation,
But I know a path without meditation.

etc.