Baba explained about sahavas with a Master:
The easiest and shortest way to God-Realization is through the contact of a Sadguru, which means keeping the company, or sahavas, of such a Master, obeying him and serving him. This remedy is like a special express train which carries you straight to your destination.
The second way is to repeat with all love and in all sincerity any one name of God, and in the absence of a Sadguru to serve humanity selflessly. This is like a journey by passenger train which halts at almost every station.
The third method takes a very long time. It means performing all the rites and ceremonies of one’s religion wholeheartedly and faithfully, but not mechanically. This method is like a freight train chugging along very slowly.
–www.lordmeher.org, p806