One verse

Srimad Bhagavatam 3.28.12

3.28.12

यदा मन: स्वं विरजं योगेन सुसमाहितम् । काष्ठां भगवतो ध्यायेत्स्वनासाग्रावलोकन: ॥ १२ ॥

yada manah svam virajam yogena susamahitam kastham bhagavato dhyayet sva-nasagravalokanah

yada
when
manah
the mind
svam
own
virajam
purified
yogena
by yoga practice
su-samahitam
controlled
kastham
the plenary expansion
bhagavatah
of the Supreme Personality of Godhead
dhyayet
one should meditate upon
sva-nasa-agra
the tip of one’s nose
avalokanah
looking at.

When the mind is perfectly purified by this practice of yoga, one should concentrate on the tip of the nose with half-closed eyes and see the form of the Supreme Personality of Godhead.