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.
(..) the th and th Century... were dedicated to a pagan god of war, Odin. Cramped by the confines of their barren, icebound northlands... they exploited their skill as shipbuilders... (..)1958 The Vikings