Ud 5:1 The King (Rājan Sutta)
I have heard that on one occasion the Blessed One was staying near Sāvatthī at Jeta’s Grove, Anāthapiṇḍika’s monastery. And on that occasion King Pasenadi Kosala had gone with Queen Mallikā to the upper palace. Then he said to her, “Mallikā, is there anyone dearer to you than yourself?”
“No, great king. There is no one dearer to me than myself. And what about you, great king? Is there anyone dearer to you than yourself?”
“No, Mallikā. There is no one dearer to me than myself.”
Then the king, descending from the palace, went to the Blessed One and, on arrival, having bowed down to him, sat to one side. As he was sitting there, he said to the Blessed One, “Just now, lord, when I had gone with Queen Mallikā to the upper palace, I said to her, ‘Mallikā, is there anyone dearer to you than yourself?’
“When this was said, she said to me, ‘No, great king. There is no one dearer to me than myself. And what about you, great king? Is there anyone dearer to you than yourself?’
“When this was said, I said to her, ‘No, Mallikā. There is no one dearer to me than myself.’”
Then, on realizing the significance of that, the Blessed One on that occasion exclaimed:
Searching all directions
with your awareness,
you find no one dearer
than yourself.
In the same way, others
are thickly dear to themselves.
So you shouldn’t hurt others
if you love yourself.