The word eid has its origin in the Arabic term ‘awd’ which means to return. In this sense, Eid is the day of return of man towards his Lord. After passing through the holy month of Ramadan in which a believer purifies his soul, he may find his original fitra, or nature, once again. Man may find himself free from the burden of sins and find that he is better connected to his creator. So in this way, he leaves behind a life of heedlessness and instead, returns to his Lord, reverting to the original nature in which man has been created. This original nature is that of purity and tranquility and the rigorous training of soul in the blessed month of Ramadan makes us shed the uncleanliness of material desires and return to that original self of purity.
Eid is a celebration. It’s a celebration similar to the day of rewards when a meritorious student receives his rewards for performing best in exams. It’s a day of joy, a joy born out of the feeling of being reconnected to a long lost love. The Lord whose mercy precedes and exceeds His punishment and Who has made mercy incumbent upon Himself for His creatures, has declared this day as the day of celebration, is the love that has been found. It’s a celebration for all those whose fasts and prayers have been accepted and who have attained the purpose of fasting, as Imam Ali (a) is quoted to have said: “Verily, it is only a festival for he whose fasts Allah has accepted and whose prayers He has acknowledged, and every day in which we do not disobey Allah is a day of celebration.” 
The day of Eid is also one of happiness and thankfulness. It’s an occasion for happiness because a believer has returned to His Lord with a clean soul and so he celebrates the day with prayers, clean clothing, perfume, and so forth. It’s an occasion for gratitude as well because Allah (swt) provided a whole month for purification and bestowal of mercy. That being said, Eid is not merely a day of merrymaking and enjoyment. We as Muslims should celebrate with festivals of special remembrance of Allah (swt) and with special thanks to Him for all the blessings and mercy. We must take care on this blessed day that our celebration should not belie the actual purpose and meaning of Eid. We shouldn’t be celebrating the release of accursed Satan but rather our release from the confines of sins, and reconstruction and revival of our original nature.
The two recommended surahs, or chapters, (Chapter 87, Al A’laa, and Chapter 97, Ash-Shams) that are read in the Eid prayers admonish us about remembrance of Allah and that success being only for those who purify themselves. The holy Quran emphasizes on remembrance: “Therefore do remind, surely reminding does profit,” (87:09) and who will mind the reminding? “He who fears will mind. “(87:10) The month of Ramadan has the purpose of cleaning rusted souls so that reminding works and ends in success for the believers: “He indeed shall be successful who purifies himself, And magnifies the name of his Lord and prays.”(87:14-15) The day of Eid is truly the day of success for the believers on which they should thank and praise their Lord.
The month long fasting if done with due honor, surely raises us to lofty levels of spirituality. Ramadan clears the dust so that the right direction becomes clearer for the soul who purifies: “And the soul and Him Who made it perfect, Then He inspired it to understand what is right and wrong for it; He will indeed be successful who purifies it, And he will indeed fail who corrupts it.” (91:7-10) This Eid, let us ask ourselves, have we purified our souls? Have we returned to Allah (swt)? This will measure our success in the month of Ramadan.
 Mizan ul Hikmah, (The Scale of Wisdom A Compendium of Shia Hadith), 1397.