"When the Imperceptible Lord reveals His ownself to man, then is he blessed with the knowledge, which the Yogis think they obtain through breath control in the central, left and right bronchi. Nanak, the True Lord is above the three devices of breath control." (Guru Nanak, Siddh Gosh, pg. 944)

"Making the still of the circuitious chord, whosoever practises the inly-washing, inhalation, exhalation and suspension of breath; Without the True Guru, he obtains not right understanding and straying in doubt he is drowned." (Guru Nanak, Parbhati, pg. 1343)

"The yoga of the pious person is this, that through the Guru's instruction, he searches his own-self and enshrines within his mind the One Lord, the Enemy of pride. Imbued with the Name, his mind becomes steady. This alone is the sublime avocation. He the detached one enters not into religious controversies and practices not hypocrisy, but by Guru's grace reflects on the Lord's Name. He, who practices chastity and truth and ponders over the Name is the pious Yogi, who practices the real yoga." (Guru Nanak, Ramkali, pg. 908)

"This is the quintessence of the Divine discourse, hear thou O Yogi, that without the Name yoga is practiced not. They who are imbued with the Name, remain inebriated night and day. Through the Name attain they the peace. All become renowned through the Name. It is through the Name, that understanding is attained. Without the Name, men wear many religious garbs and them the True Lord has Himself strayed. From the True Guru, the Name is attained, O Yogi and then one comes to know the way of Yoga. Reflect thou in thy mind and see that without the Name, one is emancipated not, O Nanak." (Guru Nanak, Siddh Gosh, pg. 946)

"Be assured that fruitless are his Yogic practices and sacrificial feasts, who forgets the Lord's praise. He who laying aside both his self-conceit and worldly love sings the praise of the Lord, Says Nanak, the mortal of such a type is said to have obtained emancipation whilst alive." (Guru Tegh Bahadur, Bilawal, pg. 831)

"He is the Yogi and he alone finds the way, who has obtained the Name, through the Guru. In that Yogi's body hamlet all the virtues abide. Through religious pretensions one attains not the True Yoga. Nanak, such a Yogi is rare within whose mind the Lord manifests Himself." (Guru Amar Das, Slok, pg. 556)

(Guru Nanak, Suhi, pg. 730)
There is but One God, By the True Guru's grace, He is obtained.
Yoga is not in the patched coat, nor the Yoga is in staff, nor Yoga is in smearing the body with ashes.
Yoga consists not in earrings, or in shaven head and Yoga is not even in the blowing of the horn.
Abide pure amidst the worldly impurities. Thus shalt thou find the way of Yoga.
By mere words Yoga is obtained not.
He is called a Yogi who looks upon all mortals with the same eye and deems them as equal.
Yoga consists not in wandering to yonder tombs, or crematoriums, or sitting in trance.
Yoga consists not in wandering in native and foreign lands, nor in bathing at places of pilgrimage.
Abide thou pure amid the worldly impurities. Thus shalt thou find the way of Yoga.
If man meets with the True Guru, then is his doubts dispelled and the wandering mind is restrained.
It rains Nectar, celestial music plays and from within his mind, man obtains gnosis.
Remain thou pure amid impurities. Like this shalt thou find the way of Yoga.
Nanak in the midst of life be thou in death. Practice thou such a Yoga.
When the horn blows within being blown, then shalt thou obtain the fearless status.
When man remains detached amidst worldly attachments, then attains he the way of Yoga.