When the mind is in Kali Yuga ...

When the mind is in Kali Yuga it appears that there are few embodiments of Guru. Due to impurities in the mind it also does not recognize Guru when it is encountered and does not treat its embodiment with due respect. Even common courtesy in salutations, sAttvic conduct acknowledging grace of teaching, or even the humility to engage in minor chores is hard to find in sAdhakas in Kali Yuga, let alone Guru seva! With such big egos it is hard for sAdhakas to even identify the genuine embodiment of Guru, let alone benefit from the teaching.

However, as the mind is purified, it transcends time; as in the Yoga Sutra it is mentioned how the sequencing of time is finally revealed IV.33

क्षणप्रतियोगी परिणामापारान्तनिर्ग्राह्य: क्रम: ।

Thoughts presented to the mind are actually a series of discrete events, each corresponding to the merest instant of time, in which one form becomes another.

With this revelation the mind transcends time and can range over all the  Yugas.

 Then it can get teaching directly from KRShNa in dvApara, from VasiShTha in treta or Brahma in satya. It can also get direct upadesha from shiva or other ciranjIvi gurus such as the three: SrI Adi ShankarAcArya, SrI RamANa MahaRShi and SrI RAmakRShNa.