As Salaamu Alaykum ikhwaan.
The Day of 'Arafah is a special and blessed day! Allah completed and perfected His Deen for us on 'Arafat:
"This day those who disbelieve have dispaired of [defeating] your religion; so fear them not, but fear Me. This day I have perfected for you your Deen and completed My favor upon you and have approved for you Islam as your way of life." - Qur'an Surah al-Ma'idah (#5), verse #3.
This verse was revealed to Prophet Muhammad (may Allah bless him and grant him peace) on his one and only Hajj, on Jumu'ah the 9th of Dhul-Hijjah - which is 'Arafah.
عن أبي قتادة رضي الله عنه قال سئل رسول الله صلى الله عليه وسلم عن صوم يوم عرفة قال ((يكفر السنة الماضية والباقية)) رواه مسلم
It has been narrated on the authority of Abu Qataadah (may Allah be pleased with him) that the Messenger of Allah (may Allah bless him and grant him peace) was asked about fasting on the Day of 'Arafah. He replied, "It atones for the sins committed the previous year and the following year." - This hadith was related by Muslim and can also be found in Imām an-Nawawi's Gardens of the Righteous.
The Day of 'Arafah is the 9th of Dhul-Hijjah (which falls on Tuesday August 21, 2018 in Pittsburgh, Pennsylvania ) which is also the day before the 'Eid.
Thus, we are encouraging everyone who is able and eager to have 2 years of sins forgiven by Allah to fast on this day. May Allah give us tawfeeq!
- Your Brother
Imam Na'eem Abdullah