He 'dedicated' [='devoted'] his life/time 'to' helping the poor. = He 'dedicated himself to' helping the poor. [=he used his time, energy, etc., to help the poor]
We have a 'dedicated' phone line for our computer. [=a phone line that we use only for our computer]
They are a group of highly 'dedicated' [='committed', 'enthusiastic'] individuals.
(..) I'll stay, I'll heel, I'll even shake hands. Bark, bark? So, without a family of my own... I dedicated myself to the pursuit of knowledge... Yay! And then, I devoted myself to helping mankind. I pioneered new techniques (..)2014 Mr. Peabody & Sherman