Luis' slumber was probably the weirdest sleep that he ever had. His dream is basically not a dream but it is a rewinded memory of what happened when he talked with the spirit of the Tree of Life. The fact that the Tree of Life advised him to change his perspective of himself resonated deep in his soul. He was insecure and he knew that.
'Is that a sign that signals him to change?'
The experience of talking with the spirit of the Tree of Life was played once again in his mind at that very moment.
The thoughts and feelings that he had that time sprung in his chest as if it is happening now, especially the time when the Tree of Life confirmed that the lords before him are deliberately neglecting the moon elves to some extent!
Even that Gwendolyn dude that he praised subconsciously-- for being known for his unparalleled talent in using magic and mana even though he is a moon elf-- Luis' respect for that predecessor of his fell straight to the gutter.