In one Sutra Buddha illustrates "the rarity of human birth and its unique advantage" by giving the following analogy.

He asks his disciples; ‘Suppose there existed a vast and deep ocean the size of this world, and on its surface there floated a golden yoke, and at the bottom of the ocean there lived a blind turtle who surfaced only once in every one hundred thousand years.

How often would that turtle raise its head through the middle of the yoke?’
His disciple, Ananda, answers that, indeed, it would be extremely rare.

In this context, the vast and deep ocean refers to samsara – the cycle of impure life that we have experienced since beginningless time, continually in life after life without end – the golden yoke refers to Buddha dharma, and the blind turtle refers to us.

Although we are not physically a turtle, mentally we are not much different; and although our physical eyes may not be blind, our wisdom eyes are.

For most of our countless previous lives we have remained at the bottom of the ocean of samsara, in the three lower realms – the animal, hungry ghost and hell realms – surfacing only once in every one hundred thousand years or so as a human being.

Even when we briefly reach the upper realms of samsara’s ocean as a human being, it is extremely rare to meet the golden yoke of Buddha dharma: the ocean of samsara is extremely vast, the golden yoke of Buddha dharma does not remain in one place but moves from place to place, and our wisdom eyes are always blind.

For these reasons, Buddha says that in the future, even if we obtain a human rebirth, it will be extremely rare to meet Buddha dharma again; meeting a true Dharma Master is even more rare than this.

We can see that the great majority of human beings in the world, even though they have briefly reached the upper realm of samsara as human beings, have not met Buddha Dhamma. This is because their wisdom eyes have not opened.

What does ‘meeting Buddha dharma’ mean? It means entering into Buddhism by sincerely seeking refuge in the Triple Gems (Buddha, His Teachings and all the Masters), and thus having the opportunity to enter and make progress on the path to enlightenment.
If we do not meet Buddha dharma we have no opportunity to do this, and therefore we have no opportunity to accomplish the pure and everlasting happiness of enlightenment, the real meaning of human life.

Right now we have obtained a human rebirth and have the opportunity to attain enlightenment through Dharma practice, so if we waste this precious opportunity in meaningless activities there is no greater loss and no greater foolishness. This is because in the future such a precious opportunity will be extremely hard to find.

Source: Buddhist Anecdote FB , Drukgeney, fb