The Prophet (saws) said: The best number of companions is four, the best number in expeditions four hundred, and the best number in armies four thousand; and twelve thousand will not be overcome through smallness of numbers.

Abu Dawud said: What is correct is that this tradition is mursal (i.e. the link of the Companion is missing).

A hadith like this has been narrated on the authority of Humaid with the same chain of transmitters.

When Allah's Apostle went to bed, he used to sleep on his right side and then say, "All-ahumma aslamtu nafsi ilaika, wa wajjahtu wajhi ilaika, wa fauwadtu `Amri ilaika, wa alja'tu zahri ilaika, raghbatan wa rahbatan ilaika. La Malja'a wa la manja minka illa ilaika. Amantu bikitabika al-ladhi anzalta wa nabiyyika al-ladhi arsalta! Allah's Apostle said, "Whoever recites these words (before going to bed) and dies the same night, he will die on the Islamic religion (as a Muslim).

The Prophet said "The most superior way of asking for forgiveness from Allah is: O Allah, You are my Lord, there is none worthy of worship except You. You have created me, and I am Your servant, and I am faithful to Your covenant and promise as much as I can. I seek refuge in You from the evil of what I have done. I acknowledge Your blessings upon me, and I admit my sins. So forgive me, for none forgives sins except You.
(Allahumma anta Rabbi la ilaha illa anta, Khalaqtani wa ana `Abduka, wa ana `ala `ahdika wa wa`dika mastata`tu, A`udhu bika min Sharri ma sana`tu, abu'u Laka bini`matika `alaiya, wa abu'u laka bidhanbi faghfir lee fa innahu la yaghfiru adhdhunuba illa anta) "
The Prophet added. "If somebody recites it during the day with firm faith in it, and dies on the same day before the evening, he will be from the people of Paradise; and if somebody recites it at night with firm faith in it, and dies before the morning, he will be from the people of Paradise."

The Prophet used to invoke Allah with the following invocation: 'Rabbi-ghfir-li Khati 'ati wa jahli wa israfi fi `Amri kullihi, wa ma anta a'lamu bihi minni. Allahumma ighfirli khatayaya wa 'amdi, wa jahli wa jiddi, wa kullu dhalika'indi. Allahumma ighrifli ma qaddamtu wa ma akhartu wa ma asrartu wa ma a'lantu. Anta-l-muqaddimu wa anta-l-mu'akh-khiru, wa anta 'ala kulli shai'in qadir.'

When the Prophet got up at night to offer the night prayer, he used to say: "Allahumma laka l-hamdu; Anta nuras-samawati wal ardi wa man fihinna. wa laka l-hamdu; Anta qaiyim as-samawati wal ardi wa man flhinna. Wa lakaI-hamdu; Anta-l-,haqqun, wa wa'daka haqqun, wa qauluka haqqun, wa liqauka haqqun, wal-jannatu haqqun, wannaru haqqun, was-sa atu haqqun, wan-nabiyyuna huqqun, Mahammadun haqqun, Allahumma laka aslamtu, wa Alaika tawakkaltu, wa bika amantu, wa ilaika anabtu, wa bika Khasamtu, wa ilaika hakamtu, faghfirli ma qaddamtu wa ma akh-khartu, wa ma asrartu, wa ma a'lantu. Anta al-muqaddimu, wa anta al-mu-'akhkhiru. La ilaha il-la anta (or La ilaha ghairuka)"

The Prophet used to invoke Allah, saying, "Allahumma ighfirli khati'ati wa jahli wa israfi fi `Amri, wa ma anta a-'lamu bihi minni. Allahumma ighfirli hazali wa jiddi wa khata'i wa amdi, wa kullu dhalika 'indi."

Another chain reports a similar hadith.

The Prophet used to teach us the Istikhara for each and every matter as he used to teach us the Suras from the Holy Qur'an. (He used to say), "If anyone of you intends to do something, he should offer a two-rak`at prayer other than the obligatory prayer, and then say: 'Allahumma inni astakhiruka bi'ilmika, wa astaqdiruka biqudratika, wa as'aluka min fadlika-l-'azim, fa innaka taqdiru wala aqdiru, wa ta'lamu wala a'lamu, wa anta'allamu-l-ghuyub. Allahumma in kunta ta'lamu anna hadha-lamra khairun li fi dini wa ma'ashi wa 'aqibati `Amri (or said, fi 'ajili `Amri wa ajilihi) fa-qdurhu li, Wa in kunta ta'lamu anna ha-dha-l-amra sharrun li fi dini wa ma'ashi wa 'aqibati `Amri (or said, fi ajili `Amri wa ajilihi) fasrifhu 'anni was-rifni 'anhu wa aqdur li alkhaira haithu kana, thumma Raddani bihi," Then he should mention his matter (need).

The people said, "O Allah's Apostle ! How may we send Salat on you?" He said, "Say: Allahumma Salli 'ala- Muhammadin wa azwajihi wa dhurriyyatihi kama sal-laita 'ala `Ali Ibrahim; wa barik 'ala Muhammadin wa azwajihi wa dhurriyyatihi kamabarakta 'ala `Ali Ibrahim innaka hamidun majid."

That the Prophet advised a man, saying, "If you intend to lie down (i.e. go to bed), say, 'Allahumma aslamtu nafsi ilaika wa fauwadtu `Amri ilaika, wa wajjahtu wajhi ilaika wa alja'tu zahri ilaika, reghbatan wa rahbatan ilaika. La malja'a wa la manja minka illa ilaika. Amantu bikitabikal-ladhi anzalta; wa nabiyyikalladhi arsalta.' And if you should die then (after reciting this before going to bed) you will die on the religion of Islam"

When we prayed with the Prophet we used to say, "Peace be on Allah from His slaves and peace be on so and so." The Prophet said, "Don't say As-Salam be on Allah, for He Himself is As-Salam, but say, at-tahiyatu li l-lahi wa s-salawatu wa t-taiyibat. As-salamu `alaika aiyuha n-Nabiyu wa rahmatu l-lahi wa barakatuh. As-salamu `alaina wa `ala `ibadi l-lahi s-salihin. (If you say this then it will reach all the slaves in heaven or between heaven and earth). Ash-hadu al la-ilaha illa l-lah, wa ash-hadu anna Muhammadan `Abduhu wa Rasuluh.' Then select the invocation you like best and recite it." (See Hadith No. 794, 795 & 796).

We used to pray behind the Prophet and used to say: "As-Salamu 'Al-Allah. The Prophet said, "Allah himself is As-Salam (Name of Allah), so you should say: 'at-Tahiyatu lil-lahi was-sala-watu wattaiyibatu, as-salamu `alaika aiyyuha-n-nabiyyu wa rahmatu-l-lahi wa barakatuhu, as-salamu `alaina wa `ala `ibadi-l-lahi as-salihin. Ashhadu an la ilaha il-lallah, wa ash-hadu anna Muhammadan `abduhu wa rasuluhu."'

Allah's Apostle said to me, "When you want to go to bed, perform ablution as you do for prayer, then lie down on your right side and say: 'Allahumma aslamtu wajhi ilaika, wa fawwadtu 'amri ilaika wa alja'tu dhahri ilaika, raghbatan wa rahbatan ilaika, la malja'a wa la manja minka illa ilaika. Amantu bikitabik al-ladhi anzalta wa binabiyyika al-ladhi arsalta'. If you should die then (after reciting this) you will die on the religion of Islam (i.e., as a Muslim); so let these words be the last you say (before going to bed)" While I was memorizing it, I said, "Wa birasulika al-ladhi arsalta (in Your Apostle whom You have sent).' The Prophet said, "No, but say: Wa binabiyyika al-ladhi arsalta (in Your Prophet whom You have sent).

We said, "O Allah's Apostle! (We know) this greeting (to you) but how shall we invoke Allah for you?" He said, "Say! Allahumma salli ala Muhammadin `Abdika wa rasulika kama- sallaita 'ala all Ibrahim wa barik ala Muhammadin wa'ala all Muhammadin kama barakta 'ala all Ibrahim.' Al-Laith said: 'Ala Muhammadin wa 'ala all Muhammadin kama barakta ala all Ibrahim.

Narrated Ibn Abi Hazim and Ad-Darawardi:

Yazid said, "Kama sallaita ala Ibrahima wa barik 'ala Muhammad in wa all Muhammadin kama barakta 'ala Abrahima wa all Ibrahim."

We said, "O Allah's Apostle This is (i.e. we know) the greeting to you; will you tell us how to send Salat on you?" He said, "Say: 'Allahumma Salli 'ala Muhammadin `Abdika wa rasulika kama sal-laita 'ala Ibrahima wa barik 'ala Muhammadin wa all Muhammadin kama barakta 'ala Ibrahima wa `Ali Ibrahim."