I cannot find that sutta. If you can provide a link to the Pāli sutta, I can take a look at it. The way to provide a link is explained here:
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– Please provide a link to the Pali sutta always.
In any case, I have seen translations of the word tathāgata as “Thus Gone One”.
But the meaning of the word tathāgata is explained in the “Loka Sutta (Iti 112)“.
I have made a few “improvements” to the English translation there:
“Bhikkhus, the world has been fully understood by the Tathāgata; the Tathāgata is released from the world. The origin of the world (with suffering) has been fully understood by the Tathāgata; the causes for the origin of the world have been understood and by the Tathāgata. The cessation of the world has been fully understood by the Tathāgata; the cessation of the world has been realized by the Tathāgata. The path leading to the cessation of the world has been fully understood by the Tathāgata; the path leading to the cessation of the world has been followed by the Tathāgata.
“Bhikkhus, in the world with its devas, māras, and brahmās, with its recluses and brahmins, among humankind with its princes and people, whatever is seen, heard, sensed, cognized, attained, sought, and reflected upon by the mind—that is fully understood by the Tathāgata: therefore he is called the Tathāgata.
“Bhikkhus, from the night when the Tathāgata awakened to unsurpassed full enlightenment until the night when he passes away into the Nibbāna-element with no residue left, whatever he speaks and explains—all that is correct and not otherwise: therefore he is called the Tathāgata.
“As the Tathāgata says, so he does; as the Tathāgata does, so he says: therefore he is called the Tathāgata.
“In the world with its devas, māras, and brahmās, with its recluses and brahmins, among humankind with its princes and people, the Tathāgata is the conqueror, unvanquished, all-seer, wielding power: therefore he is called the Tathāgata.”
By knowledge of the whole world,
The whole world as it truly is,
He is released from all the world,
From all the world he is unattached.
The all-conquering heroic sage,
Freed from every bond is he;
He has reached that perfect peace,
Nibbāna which is free from fear.
Rid of taints, he is enlightened,
Trouble-free, with doubts destroyed,
Reached the final end of deeds,
Released by clinging’s full destruction.
The Enlightened One, the Lord,
The best is he, unsurpassed;
For in the world together with its devas
He set the Dhamma-wheel in motion.
Thus those devas and human beings,
Gone for refuge to the Buddha,
On meeting him pay homage to him,
Upon being released from suffering.
Tamed, of the tamed he is the best;
Calmed, of the calmed he is the seer;
Freed, of the freed he is the foremost;
Crossed, of the crossed he is the chief.
Thus do they pay him due homage,
The greatest freed from suffering:
In the world together with its devas
There is no equal.