Is "If a person's resolve is attached to what is beyond the Throne, he will attain it" a Prophetic Hadith, and if so, what is its chain of narration and explanation?

There is no hadith with this wording or meaning narrated from the Prophet, peace and blessings be upon him. This is unlikely, as the Throne is the ultimate limit of creation. High aspiration is considered one of the greatest means of elevating a person to the highest ranks, while its degradation leads to the lowest depths. Sound intention and high aspiration elevate their possessor, whereas their decline indicates weakness and sickness of the soul. Therefore, a Muslim must have high aspirations and always strive for the best for himself, his community, and his Ummah, just as Umar ibn Abd al-Aziz did when he yearned for Paradise after attaining the Caliphate.