The opposite of sunnah is
''bidi'a'' [innovation]that is to make, as law,
what Allah has not permitted to be made law, or
to bring something in religion which is not
among.
It is what the Holy Prophet S.A.W referred to
saying ''Whosoever adds to our religion is to be
rejected'' The Holy Prophet S.A.W said: ''
Follow my SUNNAH and the SUNNAH of the
well guided Caliphs after me.
Take firm hold of it with hands and teeth
[molars]. Beware of innovations [bidi'a]for every
innovation in religion is ''DHALALAH'' [an act
of going astray]. The Messenger of Allah S.A.W
referred to its happening saying ''My Ummah will
be divided into seventy three [73] sects all of
which will be thrown to hell fire except one". HE
S.A.W specified this sect saying ''They are those
who follow the way I and my Companions
follow."
Allah cleansed the Prophet S.A.W of the people
of bidi'a in the following verse: Allah the Most
High said: Verily, those who divide their religion
and break in to sects [all kind of religious sects]
You [O Muhammad S.A.W] have no concern in
them in the least. Their affair is only with Allah.
[QUR'AN 6:159]

Haq