の言葉を

someone’s words; what someone said, as the object of a verb

→ の
phrase Common #4,656
someone’s words; what someone said, as the object of a verb の indicates whose words they are, and を marks them as the object.
JA: 先生の言葉を忘れない。
EN: I won’t forget my teacher’s words.

兄の言葉を聞いてくれ

Listen to what my older brother has to say.

— さらば、わが愛/覇王別姫 (1993)

あいつの言葉を信じられるのか?

Can you really believe what he says?

従業員も一緒に顧客からの賛辞の言葉を読むことができた。

The employees were also able to read the words of praise from the customers.

彼女は自分の著書の中で、彼の支援に感謝の言葉を述べた。

In her book, she expressed her gratitude for his support.

お父様の言葉を聞くことね

You must listen to what your father says.

— インディ・ジョーンズ/最後の聖戦 (1989)

彼女は彼の有益な助言に対して、感謝の言葉を述べた。

She expressed her gratitude for his valuable advice.

僕はファイの言葉を届けに来た

I’ve come to deliver Fai’s message.

— ブエノスアイレス (1997)

誰もがトムの言葉を信じた。

Everyone believed Tom's words.

彼は我々全員に感謝の言葉を述べた。

He expressed his gratitude to all of us.

先生の言葉を忘れない。

I will never forget my teacher’s words.