Wise person keeps pace with the modern era (5,3)
I believe the answer is:
space age
'the modern era' is the definition.
(I've seen this before)
'wise person keeps pace' is the wordplay.
'wise person' becomes 'sage' (sage can mean a wise or holy person).
'keeps' means one lot of letters goes inside another (inserted letters are kept inside).
'sage' placed around 'pace' is 'SPACE-AGE'.
'with' is the link.
(Other definitions for space age that I've seen before include "Modern times" , "(Technologically) highly advanced" , "modern era" , "Now we can travel so far!" , "The time of our lives" .)