Tao Te Ching, 7

Heaven is eternal and Earth everlasting.

They can be eternal and everlasting because they do not exist for themselves,

And for this reason can exist forever (Tao Te Ching, 7)

Today, I would try to interpret the above text.

It is indicated above that the Heaven and Earth are eternal and everlasting because they do not exist for themselves. This means that the idea of the two are not anymore thought of by the people because they are now harmonized by the Tao. Aside from the harmonization of the Tao, the two opposites are not anymore distinguished by man because he understood that opposites are natural and they would always exist. He has learned to let them do their ways and did the unlearning to suspend judgments and prejudices. Because of this, he knew how not to differentiate the opposites.

The two are eternal and everlasting. They do not exist because man has learned not to treat them as contradictory to the other rather as a complementary aspect of the partner. Understanding their existence in that way makes them non existing ideas. In another sense, they exist forever in a way that they are understood by man by their natural idea. Man has learned to suspend his biases over them and tried to understand them by the way they truly are based on their natural idea.