The twelfth chapter of the Bhagavad Gita is Bhakti Yoga. In this chapter, Krishna emphasizes the superiority of Bhakti Yoga (the path of devotion) over all other types of spiritual disciplines and reveals various aspects of devotion. He further explains that the devotees who perform pure devotional service to Him, with their consciousness, merged in Him and all their actions dedicated to Him, are quickly liberated from the cycle of life and death. He also describes the various qualities of the devotees who are very dear to Him.
Arjuna said: Those devotees who, being thus ever dedicated, meditate on You, and those again (who meditate) on the Immutable, the Unmanifested-of them, who are the best experiencers of yoga [(Here) yoga means samadhi, spiritual absorption.] ?OPEN VERSE
The Blessed Lord said: Those who meditate on Me by fixing their minds on Me with steadfast devotion (and) being endowed with supreme faith-they are considered to be the most perfect yogis according to Me.OPEN VERSE
Those, however, who meditate in every way on the Immutable, the Indefinable, the Unmanifest, which is all-pervading, incomprehensible, change-less, immovable and constant. By fully controlling all the organs and always being even-minded, they, engaged in the welfare of all beings, attain Me alone.OPEN VERSE
For them who have their minds attached to the Unmanifested the struggle is greater; for, the Goal which is the Unmanifest is attained with difficulty by the embodied ones.OPEN VERSE
As for those who, having dedicated all actions to Me and accepted Me as the supreme, meditate by thinking of Me with single-minded concentration only-.OPEN VERSE