One verse

Srimad Bhagavatam 11.20.35

11.20.35

नैरपेक्ष्यं परं प्राहुर्नि:श्रेयसमनल्पकम् । तस्मान्निराशिषो भक्तिर्निरपेक्षस्य मे भवेत् ॥ ३५ ॥

nairapekṣyaṁ paraṁ prāhur niḥśreyasam analpakam tasmān nirāśiṣo bhaktir nirapekṣasya me bhavet

nairapekṣyam
not desiring anything except devotional service
param
the best
prāhuḥ
it is said
niḥśreyasam
highest stage of liberation
analpakam
great
tasmāt
therefore
nirāśiṣaḥ
of one who does not seek personal rewards
bhaktiḥ
loving devotional service
nirapekṣasya
of one who only sees Me
me
unto Me
bhavet
may arise

It is said that complete detachment is the highest stage of freedom. Therefore, one who has no personal desire and does not pursue personal rewards can achieve loving devotional service unto Me.