Heaven and Earth (Creation) is eternal.
The reason why Creation is eternal is because the Creator did not create it for Himself.
Selflessness is what makes it everlasting.
The sage puts others before himself, and thus leads.
He does not consider his own risks while helping others, so the risk causes no harm to him.
It causes no harm to him because of his selflessness.
That is why he can attain the success of others and as a result, his own.
(That is why he can benefit others and as a result, himself.)
Implications from the Holy Books
It behooveth every king to be as bountiful as the sun, which fostereth the growth of all beings, and giveth to each its due, whose benefits are not inherent in itself, but are ordained by Him Who is the Most Powerful, the Almighty. The King should be as generous, as liberal in his mercy as the clouds, the outpourings of whose bounty are showered upon every land, by the behest of Him Who is the Supreme Ordainer, the All-Knowing. —Bahá’u’lláh, Gleanings From the Writings of Bahá’u’lláh 114
The Ancient Beauty hath consented to be bound with chains that mankind may be released from its bondage, and hath accepted to be made a prisoner within this most mighty Stronghold that the whole world may attain unto true liberty. He hath drained to its dregs the cup of sorrow, that all the peoples of the earth may attain unto abiding joy, and be filled with gladness. This is of the mercy of your Lord, the Compassionate, the Most Merciful. We have accepted to be abased, O believers in the Unity of God, that ye may be exalted, and have suffered manifold afflictions, that ye might prosper and flourish. He Who hath come to build anew the whole world, behold, how they that have joined partners with God have forced Him to dwell within the most desolate of cities! —Bahá’u’lláh, Gleanings From the Writings of Bahá’u’lláh 45