One verse

Srimad Bhagavatam 11.9.31

11.9.31

न ह्येकस्माद् गुरोर्ज्ञानं सुस्थिरं स्यात् सुपुष्कलम् । ब्रह्मैतदद्वितीयं वै गीयते बहुधर्षिभि: ॥ ३१ ॥

na hy ekasmād guror jñānaṁ su-sthiraṁ syāt su-puṣkalam brahmaitad advitīyaṁ vai gīyate bahudharṣibhiḥ

na
not
hi
certainly
ekasmāt
from one
guroḥ
guru
jñānam
knowledge
su-sthiram
very steady
syāt
can be
su-puṣkalam
very complete
brahma
the Absolute Truth
etat
this
advitīyam
one without a second
vai
certainly
gīyate
is glorified
bahudhā
in many ways
ṛṣibhiḥ
by the sages

Although the Absolute Truth is one without a second, the sages have described Him in many different ways. Therefore one may not be able to acquire very firm or complete knowledge from one spiritual master.