xnat01 peer authentication failed

postgres@klein:~$ psql
psql (9.4.8)
Type "help" for help.

postgres=# ALTER USER "xnat01" WITH PASSWORD "1234";
ERROR:  syntax error at or near ""1234""
LINE 1: ALTER USER "xnat01" WITH PASSWORD "1234";
                                          ^
postgres=# ALTER USER "xnat01" WITH PASSWORD '1234';
ALTER ROLE
postgres=# REVOKE CONNECT ON DATABASE xnat FROM PUBLIC;
REVOKE
postgres=# GRANT CONNECT ON DATABASE xnat FROM TO xnat01;
ERROR:  syntax error at or near "FROM"
LINE 1: GRANT CONNECT ON DATABASE xnat FROM TO xnat01;
                                       ^
postgres=# GRANT CONNECT ON DATABASE xnat TO xnat01;
GRANT
postgres=# GRANT ALL PRIVILEGES ON DATABASE xnat TO xnat01;
GRANT
postgres=# \q
postgres@klein:~$ exit
logout
jalal@klein:~/computer_vision/XNAT/xnat/deployments/xnat/sql$ psql -d xnat -f sql/xnat.sql -U xnat01
psql: FATAL:  Peer authentication failed for user "xnat01"