After the Holy Prophet's  advent, all other laws (shari'ahs) and ways of life have been abrogated. Apart from the Holy Prophet's  shar'a (law) and practice (Sunnah), nothing is acceptable; and blessing has been bestowed in his method only till the Day of Judgement. The blessing of this method is such that while in former times people could not reach this grade even after a thousand years of labours and austere practices, a Muhammadi (a follower of Muhammad) can reach it within a few years of strivings.
In short, there is great blessing in the Holy Prophet's  methods and practices, as has been said in a Hadith: "Live within the circle of the sunnah, even a small deed is auspicious and better than doing too much after involvement in innovation; and every innovation is a deviation and every deviation leads to Hell."

Similarly, the Holy Prophet  has said: "Operating within the circle of sunnah, even moderate action, is better than any great austere practices performed after being involved in innovation".

Hazrat Ibn Mas'ud  says: "To offer prayers moderately according to the sunnah method is better than labouring hard in the method of innovation".

Apart from the Holy Prophet's  method whoever adopts any carnal and satanic way will be deprived of the prophetic intercession, as it says in a Hadith that, “There are two men who will not receive my intercession: a tyrannous king and the overzealous man who may exceed so much that ultimately he may go beyond the way of the Ahl al-Sunnah wal-Jama' ah.”

Hence one should save oneself from too much exceeding and excess in religion, as also from innovations, for innovation is Satan's great net his very great stratagem.

Hazrat Ibn Abbas  says: "By Allah! I do not know if today there is any other person on the surface of the world whose death Satan may like more, than my dying" He was asked: "Why so"? He replied: "When Satan devises something new in the east or the west and any Muslim comes to me to ask the order regarding it, I guide him to the Holy Prophet's  path. Thus the Satan's innovation is thrown back on his face unused".

Moreover, the Holy Prophet  also said that even to look at a man who is following the way of the sunnah and who prevents people from following innovations and orders them to follow the sunnah way, is (a part of) devotion. Similarly, there is another Hadith to the effect that whoever fabricated an opinion which is not in the Quran nor is it in accord with the Holy Prophet's  Sunnah, he (the fabricator) does not know what his result would be tomorrow, on the Day of Judgement.