Following the predecessors

Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) says: Follow (the predecessors) and do not innovate, for you have been given sufficiency.
Tabarani recorded it in al-Mu'jam al-Kabir, and its narrators are the narrators of the Sahih.

Amr bin Salamah narrates: Once, between Maghrib and Isha, we were sitting at the door of Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him). Meanwhile Sayyiduna Abu Musa al-Ash'ari (may Allah be pleased with him) came and said: O Abu Abd al-Rahman! Come out to us. Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) came out. Sayyiduna Abu Musa (may Allah be pleased with him) said: Why have you come at this hour? He said: By Allah, I saw a matter that alarmed me. It is something good, yet it has alarmed me, even though it is something good. Some people were sitting together in a mosque, and one man among them was saying: Say "Subhan Allah" so many times! Say "Al-hamdu lillah" so many times! The narrator says: Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) set off, and we went along with him. Sayyiduna Abdullah (may Allah be pleased with him) came to those people and said: How quickly you have fallen into misguidance! Yet the Companions of the Messenger of Allah are still alive, his (peace and blessings be upon him) wives are still present, and his (peace and blessings be upon him) clothes and vessels have not yet worn out. Count your bad deeds, and I guarantee you on Allah's behalf that He will count your good deeds.
Tabarani recorded it in al-Mu'jam al-Kabir; its chain contains Mujalid bin Sa'id, whom al-Nasa'i (may Allah have mercy on him) declared thiqah (trustworthy), while al-Bukhari (may Allah have mercy on him), Ahmad bin Hanbal and Yahya declared him da'if (weak).

Abu al-Bakhtari narrates: Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) was informed that some people sit between Maghrib and Isha and say (to one another): Recite this! Recite this! Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) said: When they start doing that, inform me. When they sat down, other people came to Sayyiduna Abdullah (may Allah be pleased with him). Sayyiduna Abdullah (may Allah be pleased with him) went with them and sat down there. He had a hood on (that is, he had covered his face). When those people began their glorification, Sayyiduna Abdullah (may Allah be pleased with him) removed the hood from his head and said: I am Abdullah bin Mas'ud. The people fell silent. Sayyiduna Abdullah (may Allah be pleased with him) said: You have committed an innovation wrongfully; if that is not so, then do you have superiority over us, that is, over the Companions of Muhammad? Amr bin Utbah bin Farqad said: O Ibn Mas'ud! I seek forgiveness from Allah Almighty and turn to Him in repentance. Sayyiduna Abdullah (may Allah be pleased with him) ordered those people to disperse. The narrator says: Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) saw two circles in the mosque of Kufah, so he stood between them and asked: Which of your two circles was formed first? The members of one circle said: We (formed our circle first). Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) said to the members of the other circle: Get up and join them! Thus Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) made them a single circle.
Tabarani recorded it in al-Mu'jam al-Kabir; its chain contains Ata bin al-Sa'ib, who is thiqah (trustworthy) but suffered from mental confusion (ikhtilat). In some of Tabarani's sound chains this report is narrated in abridged form (with these words): Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) came with his head covered and said: Whoever knows me, knows me; and whoever does not know me, I am Abdullah bin Mas'ud. Are you more rightly guided than Muhammad (peace and blessings be upon him) and his Companions? Or else you are clinging to the sin of misguidance? In one narration of Ata bin al-Sa'ib the words are: Then Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) said: If you follow the people (that is, the Companions), they have already outstripped you by a great and clear distance; and if you take the path to the right and the left, you will fall into far misguidance.

Mus'ab bin Sa'd narrates: When my father (Sayyiduna Sa'd bin Abi Waqqas (may Allah be pleased with him)) prayed in the mosque, he would keep the prayer short, though he would complete the bowing and prostration; and when he prayed at home, he would make the bowing, the prostration and the prayer long. I said: O father! When you pray in the mosque you keep it short, and when you pray at home you make it long? He said: O my son! We (that is, the Companions) are leaders, and we will be followed.
Tabarani recorded it in al-Mu'jam al-Kabir, and its narrators are the narrators of the Sahih.

Khalid bin Urfutah narrates: I was sitting with Sayyiduna Umar (may Allah be pleased with him) when a man came to him who belonged to the tribe of Abd al-Qays and whose residence was in "Sus". Sayyiduna Umar (may Allah be pleased with him) asked him: Are you so-and-so, son of so-and-so, al-Abdi? He replied: Yes! So Sayyiduna Umar (may Allah be pleased with him) struck him with the staff he had with him. The man said: O Commander of the Faithful! What is my fault? Sayyiduna Umar (may Allah be pleased with him) said to him: Sit down! He sat down, and Sayyiduna Umar (may Allah be pleased with him) recited these verses before him: "Alif Lam Ra. These are the verses of the clear Book. Indeed, We have sent it down as an Arabic Qur'an so that you may understand. We relate to you the best of stories through what We have revealed to you of this Qur'an, although before it you were among the unaware." Sayyiduna Umar (may Allah be pleased with him) recited these verses before that man three times and struck him all three times. He asked: O Commander of the Faithful, what is my fault? Sayyiduna Umar (may Allah be pleased with him) said: Are you the man who copied the books of Daniyal (peace be upon him)? The man said: Give me your order and I will follow it. Sayyiduna Umar (may Allah be pleased with him) said: Go and erase that writing with hot water and clean cotton! Then never read it, nor teach anyone to read it. If it reaches me about you that you have read it or taught anyone to read it, I will punish you. Then Sayyiduna Umar (may Allah be pleased with him) said to him: Sit down! He sat down, and Sayyiduna Umar (may Allah be pleased with him) said: "Once I went and copied part of a book of the People of the Book; I wrote it down on a piece of leather and brought it. The Prophet (peace and blessings be upon him) asked me: 'O Umar! What is in your hand?' I said: O Messenger of Allah! This is a writing which I have copied so that through it our existing knowledge may increase. The Prophet (peace and blessings be upon him) became angry, until his cheeks turned red. Then it was announced: Let the people gather! The Ansar said: Has your Prophet become angry? Take up arms! Take up arms! They came and gathered around the pulpit of the Prophet (peace and blessings be upon him). The Prophet (peace and blessings be upon him) said: 'O people! Indeed, I have been given comprehensive and concluding words, things have been made concise for me, and I have come to you with clear and plain guidance. So do not become hair-splitters, and do not let the hair-splitters mislead you.'" Sayyiduna Umar (may Allah be pleased with him) says: I said: I am pleased with Allah Almighty as Lord, with Islam as religion, and with you (peace and blessings be upon him) as Messenger. Then the Prophet came down (from the pulpit).
Abu Ya'la recorded it; its chain contains Abd al-Rahman bin Ishaq al-Wasiti, whom Ahmad and a group (of scholars) declared da'if (weak).