No. You are the swiftest, but you must be steady.
3 seconds sound clip from the Ben-Hur (1959) movie soundboard.
You can hear this line at 01:49:41.392 in the Blu-ray version of the movie.
Quote context
[...]
- What? Yes, yes. Yes, I love you too. There's my good Antares.
- Come, Rigel. We've both supped well, and the world is good. There's my good Rigel.
- Good night. Good night, my treasure.
- Ah! Steady, Aldebaran. I haven't forgotten you.
- No. You are the swiftest, but you must be steady.
- Never seen finer horses, even in Rome.
- Ah, you should see their mother, Mira.
- I dare not bring her because my people couldn't bear her absence.
- You are their friend, and they do not give their affections readily.
[...]