O People, if you should be in doubt about the Resurrection, then [consider that] indeed, We created you from dust, then from a sperm-drop, then from a clinging clot, and then from a lump of flesh, formed and unformed – that We may show you. And We settle in the wombs whom We will for a specified term, then We bring you out as a child, and then [We develop you] that you may reach your [time of] maturity. And among you is he who is taken in [early] death, and among you is he who is returned to the most decrepit [old] age so that he knows, after [once having] knowledge, nothing. And you see the earth barren, but when We send down upon it rain, it quivers and swells and grows [something] of every beautiful kind.(22:5)

Narrated Anas bin Malik: In the life-time of Allah’s Apostle (p.b.u.h) the people were afflicted with a (famine) year. While the Prophet was delivering the Khutba (sermon) on the pulpit on a Friday, a Bedouin stood up and said, “O Allah’s Apostle! The livestock are dying and the families (offspring) are hungry: please pray to Allah to bless us with rain.” Allah’s Apostle raised both his hands towards the sky and at that time there was not a trace of cloud in they sky. Then the clouds started gathering like mountains. Before he got down from the pulpit I saw rain-water trickling down his beard. It rained that day, the next day, the third day, the fourth day and till the next Friday, when the same Bedouin or some other person stood up (during the Friday Khutba) and said, “O Allah’s Apostle! The houses have collapsed and the livestock are drowned. Please invoke Allah for us.” So Allah’s Apostle raised both his hands and said, “O Allah! Around us and not on us.” Whichever side the Prophet directed his hand, the clouds dispersed from there till a hole (in the clouds) was formed over Medina. The valley of Qanat remained flowing (with water) for one month and none, came from outside who didn’t talk about the abundant rain. [-] [Bukhari 017:143]

There is a polish for everything that takes away rust; and the polish for the heart is the remembrance of Allah.” (Bukhari)

http://www.boston.com/bigpicture/2011/11/the_hajj_and_eid_al-adha.html

The Messenger of Allaah (صلى الله عليه وسلم) said:
‘The days of al-Tashreeq (11th, 12th and 13th of Dhul Hijjah) are the days of eating, drinking and remembering Allah’
[Muslim]

Eid al-Adha (Arabic: عيد الأضحى‎ ‘Īd al-’Aḍḥá,”feast of sacrifice”) or “Festival of Sacrifice” or “Greater Eid” is an important religious holiday celebrated by Muslims worldwide to commemorate the willingness of Abraham (Ibrahim) to sacrifice his son Ishmael (Isma’il) as an act of obedience to God, before God intervened to provide him with a sheep— to sacrifice instead.[1]

Eid al-Adha is the latter of two Eid festivals celebrated by Muslims, whose basis comes from Sura 2 (Al-Baqara) Ayah 196 in the Qur’an.[2] Like Eid ul-Fitr, Eid al-Adha begins with a Sunnah prayer of two Raka’ah (units) followed by a sermon (khuṭbah).

The word “Eid” appears in Sura al-Mai’da (“The Table Spread,” Chapter 5) of the Qur’an, meaning ‘solemn festival’.[3]

Eid al-Adha is celebrated annually on the 10th day of the 12th and the last Islamic month of Dhu al-Hijjah (ذو الحجة) of the lunar Islamic calendar.[4] Eid al-Adha celebrations start after the Hajj, the annual pilgrimage to Mecca in Saudi Arabia by Muslims worldwide, descend from Mount Arafat. The date is approximately 70 days (2 Months & 10 days) after the end of the month of Ramadan, i.e. Eid-ul-Fitr. Ritual observance of the holiday lasts until sunset of the 13th day of Dhu al-Hijjah.[5]

“Fasting the Day of ʿArafah [9th of Dhul-Ḥijjah] is an expiation for [all the sins of] the previous year and an expiation for [all the sins of] the coming year.”

[Ṣaḥīḥ al-Muslim]

Say: “Allah knows best how long they stayed. With Him is (the knowledge of) the unseen of the heavens and the earth. How clearly He sees, and hears (everything)! They have no Wali (Helper, Disposer of affairs, Protector, etc.) other than Him, and He makes none to share in His Decision and His Rule.”

قُلِ ٱللَّهُ أَعْلَمُ بِمَا لَبِثُوا۟ ۖ لَهُۥ غَيْبُ ٱلسَّمَٰوَٰتِ وَٱلْأَرْضِ ۖ أَبْصِرْ بِهِۦ وَأَسْمِعْ ۚ مَا لَهُم مِّن دُونِهِۦ مِن وَلِىٍّۢ وَلَا يُشْرِكُ فِى حُكْمِهِۦٓ أَحَدًۭا