The Three Principal Aspects of the Path by Je Tsongkhapa
The First Principal Path: Renunciation
At the beginning, you must think of renunciation. Because if you do not have
renunciation, you cannot get detached from Samsara and you cannot get out from
Samsara. Therefore, renunciation is very important
The Second Principal Path - The Bodhi-Mind
That kind of renunciation that you have generated within yourself, if it is not
influenced by bodhimind then that renunciation cannot produce enlightenment the
complete happiness. It cannot cause complete happiness if the renunciation is
not influenced or dominated by the bodhimind. Therefore, any wise man should
generate the bodhimind.
The Third Principal Path - Ultimate Truth
You need the wisdom to know the ultimate truth, if you don't have this kind of
wisdom even if you get familiar with renunciation and bodhimind you will not be
able to cut the root of Samsara. Therefore, you must make every effort to
realize Dependent-Arising.
Read more at :
http://www.norbucholingcentre.org/downloads/three_principal_paths.pdf