replace text occurrences loaded from table

hello,

i am actually trying to replace all occurences in a text column with some value, but the occurrences to replace are
definedin a table. this is a simplified version of my schema: 

create temporary table tmp_vars as select var from (values('ABC'),('XYZ'),('VAR123')) entries (var);
create temporary table tmp_messages as select message from (values('my ABC is XYZ'),('the XYZ is very VAR123'))
messages(message); 

select * from tmp_messages;

my ABC is XYZ -- row 1
the XYZ is very VAR123 -- row 2

now i need to somehow update the rows in tmp_messages, so that after the update i get the following:

select * from tmp_messages;

my XXX is XXX -- row 1
the XXX is very XXX -- row 2

i have implemented a solution in plpgsql by doing a nested for-loop over tmp_vars and tmp_messages, but i would like to
knowif there is a more efficient way to solve this problem ? 


best regards
jan