(C) No person shall be elected or appointed to any
judicial office if on or before the day when he shall
assume the office and enter upon the discharge of its
duties he shall have attained the age of seventy years.
Any voluntarily retired judge, or any judge who is
retired under this section, may be assigned with his
consent, by the chief justice or acting chief justice of
the Supreme Court to active duty as a judge and while
so serving shall receive the established compensation
for such office, computed upon a per diem basis, in
addition to any retirement benefits to which he may
be entitled. Laws may be passed providing retirement
benefits for judges.