Aragorn on Leadership

Aragorn to Gandalf after the later asks who will follow him into Moria:

‘I will,’ said Aragorn heavily. ‘You followed my lead almost to disaster in the snow, and have said no word of blame. I will follow your lead now–if this last warning does not move you. It is not of the Ring, nor of us others that I am thinking now, but of you, Gandalf. And I say to you: if you pass the doors of Moria, beware!’