Get Rock Smash on Pokémon FireRed

Do you need the special HM move Rock Smash in Pokémon FireRed?

Steps

After defeating the Pokémon Gym Leader on Cinnabar Island, You get greeted by Bill, the guy who has the PC System.
After you'll go to the islands of One, Two, Three, etc.
Go up to the volcano on One Island(Kindle Road).
On the way there there's a hot spring sauna.
Go in the rock formation.
There will be elders.
Talk to ALL of them.
One elder will give you HM move Rock Smash.
Use wisely (as the old saying go's).

Take a dip in one of the hot spring. It will rest your Pokémon for the battle with Moltres.