The real reason is to get us away from the general. He knows he can't get near to the general while we are his bodyguards.
10 seconds sound clip from the Ninjutsu (1968) movie soundboard.
You can hear this line at 01:18:23 in the Blu-ray version of the movie.
Quote context
[...]
- Hey brother, there's bound to be traps.
- He must of met his master, and then he was told to come back here.
- They kidnapped the young master to hold him as ransom for the ninja book.
- But if we're not there, his job will be easy. But that's what he thinks.
- We'll have to go to Xiu's Garden.
- We have no choice. We must stop him.
- Yeah!
[...]