How to practice “To be in the world but not of it”?

Tom: This brings me to one common advice that I would like to ask you.

Guru: Okay, what is the advice?

Tom: To be in the world but not of it.

Guru: Oh yes, this is a common advice.

Tom: Is this a good advice?

Guru: Oh yes, it is a good advice.

Tom: But how do we practice it?

Guru: By living spiritually.

Tom: Is it good to live spiritually?

Guru: Of course it is.

Tom: But you said that we may lose many things.

Guru: Yes, I did.

Tom: I am confused.

Guru: You see in living spiritually, we may lose many worldly things.

Tom: So, we are losers.

Guru: But we’ll gain something more valuable.

Tom: Which is?

Guru: Spiritual enlightenment.

Tom: Wow, you mean we will go to heaven.

Guru: We will live on Earth as though we are in heaven.

Tom: You mean heaven on Earth.

Guru: We will have heaven inside and Earth outside.

Tom: Wow, we will then truly live in the world but not of it.