After 8.4 million bodies, you get a human body.
Just imagine, from bacteria, birds, animals, etc., 8.4 million lives later a human life comes. In this human life, few get to know the real spiritual path. And among those, very few walk on the path and they are the lucky ones.
Adi Shankara has also said, that the human birth is very difficult to get.
After having gotten human birth, the desire of wanting to walk on the spiritual path, is also very difficult to get. Few people get this. And even after getting this desire to walk on the spiritual path, only few get the opportunity to do it; they get the right path.
So many people, who want to walk on the spiritual path get caught up in all these wrong notions that one day the world is going to collapse, or doom’s day is going to come. And so these people pray out of fear. They get into paths where they are indented with fear and guilt. Fear and guilt are two things that will never allow you to go deep into yourself. And this is what some of the so called (religious) paths do.
Some of the religious paths create this fear of hell and heaven that puts people into such a turmoil of guilt and fear that the mind can never calm down. Meditation can never happen. This is very unfortunate. So even though these people are aspirants, they are not getting the path.
These people don’t get access to the knowledge: ‘Come on, the mind is like a river, what are you holding on to? Don’t hold on to it. All the events are gone, drop it and move on. Live in the present moment‘.
This knowledge is not available to many people (who aspire to walk the spiritual path). They go on repenting about the past, feeling guilty, and the mind becomes a mess.
Of course they do pray. Their prayers do help, and they get some blessings. Blessings come to everyone, no doubt, but the knowledge, the right path and liberation remains a distant dream for them. Peace does not happen in their life. They sit with the hope that one day they will go to heaven. And so these souls get trapped with desires and fear.
They get a human life to be free from all this. So they will have to come back again to work out all these things. Again they will get into meditation.
So, a human birth, desire for a path, and the path being available to them (Maha Purusha Sannidho: getting a Spiritual Master), these three things are rare and difficult to get. If you have all three, you are lucky.