Point 6---- Know that people never introduce an innovation until they abandon its like from the sunnah1. So, beware of newly invented matters, since every newly invented matter is an innovation and every innovation is misguidance and misguidance and its people are in the fire.
1 Hassan ibn 'Attiyah, rahimuAllah, said, "A people never introduce an innovation ito their religion except that Allah takes away its like from their Sunnah and then does not restore it to them until the Day of Resurrection." Reported by Ad-Daarimee and declared saheeh by Shaikh al-albani in al-Mishkaat (1/66/no.188).
Point 7--- Beware of the small innovation because they grow until they become large1. This was the case with every innovation introduced in this Ummah. It began as something small, bearing resemblance to the truth which is why those who entered it were mislead and then were unable to leave it. So it grew and became the religion which they followed and thus deviated from the Straight Path and left Islaam.2
1 'Amr ibn Salmah said, "We used to sit by the door of Abdullah ibn Mas'ood before the morning prayer, so that when he came out we would walk with him to the masjid. (One day) Abu Moosa al-Ash'aree came to us and said, 'Has Abu 'Abdurrahmaan come out yet?' We replied, 'No.' So he sat down with us until he (ibn Mas'ood) came out. When he came out we all stood along with him, so Abu Moosa said to him, 'O Abu Abdurrahmaan! I have just seen something in the masjid which I deemed to be evil, but all praise is for Allaah, I did not see anything except good.' He enquired, 'Then what is it?' (Abu Moosa) replied, 'If you live you will see it. I saw in the masjid people sitting in circles awaiting the prayer. In each circle they had pebbles in their hands and a man would say, "Repeat Allaahu Akbar a hundred times." So they would repeat it a hundred times. Then he would say, "Say Laa ilaaha illallaah a hundred times." So they would say it a hundred times. Then he would say, "Say subhaanallaah a hundred times." So they would say it a hundred times.' (Ibn Mas'ood) asked, 'What did you say to them?' (Abu Moosa) said, 'I did not say anything to them. Instead I waited to hear your view or what you declared.' (Ibn Mas'ood) replied, 'If only you had ordered them to count up the evil deeds they acquired and assured them that their good deeds would not be lost!' Then we went along with him (Ibn Mas'ood) until he came to one of these circles and stood and said, 'What is this which I see you doing?' They replied, 'O Abu Abdurrahmaan! These are pebbles upon which we are counting takbeer, tahleel and tasbeeh.' He said, 'Count up your evil deeds. I assure you that none of your good deeds will be lost. Woe to you, O Ummah of Muhammad sallallaahu 'alayhi wa sallam! How quickly you go to destruction! These are the Companions of your Prophet sallallaahu 'alayhi wa sallam and who are widespread. There are his sallallaahu 'alayhi wa sallam clothes which have not yet decayed and his bowl which is unbroken. By Him in Whose Hand is my soul! Either you are upon a religion better guided than the religion of Muhammad sallallaahu 'alayhi wa sallam or you are opening the door of misguidance.' They said, 'O Abu Abdurrahmaan! By Allaah, we only intended good.' He said, By Him in Whose Hand is my soul! Either you are upon a religion better guided than the religion of Muhammad sallallaahu 'alayhi wa sallam or you are opening the door of misguidance. Umar ibn Salmah (the sub-narrator) said, "We saw most of those people fighting against us on the day of Nahrawaan, along with the Khawaarij." (ad-Daarimee in his Sunan, 1/79) Authenticated by Saleem al-Hilaalee in al-Bid'ah (pp.26-29)
2 The scholars differentiate between those innovations which take a person outside the fold of Islam (al-Bid'atul Mukaffirah) and those which do not. So this is not to be understood unrestrictedly.
Point 8--- May Allah have mercy upon you! Examine carefully the speech of everyone you hear from in your time particularly. So do not act in haste and do not enter into anything from it until you ask and see: Did any of the Companions of the Prophet ('allayhee salat wassalam) speak about it or any of the scholars? So if you find a narration from them about it, cling to it, do not go beyond it for anything1 and do not give precedence to anything over it and thus fall into the fire.
1 Imam al-Awzaa'ee, rahimuAllah, said, "Knowledge is what comes from the Companions of Muhammad ('allayhee salat wassalam) and that which does not come from a single one of them is not knowledge". Refer to Jaami' Bayaanil-'ilm of 'Abdul Barr (2/36).
Point 9--- Know that leaving the correct path occurs in two ways. Firstly: that a man strays from the correct path intending nothing but good, so his error is not to be followed since it leads to destruction. (Secondly), a man who deliberately opposes the truth and acts contrary to the Pious ones who came before him, he is astray, leading others astray, a rebellious devil within the Ummah. It is a duty upon those who know of him to warn the people against him and to explain his condition to them so that no one falls into his innovation and is destroyed.
Point 10--- May Allah have mercy upon you! Know that a servant's Islam is not complete until he follows, attests to and submits to (the truth). So anyone who claims that there remains anything from Islam not sufficiently explain by the Companions of Allah's Messenger ('allayhee salat wassalam), has falsely accused them, has split from them and spoke ill of them. He is an innovator, astray and leading others astray, introducing into Islam that which is not from it.1
1 Ibn mas'ood, radhiAllahu 'anhoo, described the Companions of the Messenger of Allah ('allayhee salat wassalam) saying, "Allah looked into the hearts of the servants and found the heart of Muhammad to be the best of hearts, so He chose him for Himself and sent with him His Revelation, then He looked the hearts of the servants after the heart of Muhammad ('allayhee salat wassalam) and found the hearts of his Companions to be the best of the hearts of the servants, so He made them the helpers of His Prophet, fighting for His Religion. So that which the Muslims hold to be good is good with Allah and that which they hold to be bad is bad with Allah." Reported in the Musnad of Imaam Ahmad (1/379) and declared hasan by Shaikh al-Albani in ad-Da'eefah (2/17).