What does worship (ibada) mean in Islam?

The concept of Ibadah is central to Islam - it is the purpose of our existence - servitude of Allah. “And I did not create the jinn and mankind except to serve Me”. "O mankind, serve your Lord, who created you and those before you, that you may become righteous”. “And We certainly sent into every nation a messenger, [saying], “Serve Allah and avoid taghut.” The original linguistic meaning of Ibadah is “to lower one’s self”. It is also called “the path that is lowered due to feet stamping it down” and “the travelers lowered it”. From this, a mule that is lowered for riding is called “Mu’abbad”, and from this a person who is enslaved is called an “Abd”, due to his being lowered before his master. Al-Fayrooz Abaadi said in his dictionary, Al-Qamoos Al-Muheet: “Al-Ibadah: Obedience”. Al-Tabari in his Tafseer of the verse in Sura Al-Fatiha stated: “Iyyaka Na’budoo” (You we serve): “Oh Allah, it is to You alone that we have Kushoo’, that we submit to, and that we depend on, acknowledging your Lordship over us, you alone and none other than you”. Al-Zajaj said: “The meaning of Al-Ibadah: Obedience with submission”. Al-Zamakhshari said: “Al-Ibadah: The most extreme level of submission and lowering one’s self”. Ar-Raghib al-Asfahani observed: "The wilfully chosen action devoid of bodily desires which arises out of an intention and by which nearness to Allaah and obedience to the Sharee'ah is intended." (Tafseel an-Nash'atayn wa Tahseel as-Sa'aadatayn p. 157). Al-Baghawi said: “Al-Ibadah: Obedience with lowering one’s self and submission, and the slave was called abd due to his submission and his obedience.” (Sharh us-Sunnah 1/53). Ibn Taymiyyah said: "Ibadah is obedience to Allah by carrying out what He has commanded on the tongues of His messengers." He also said: "Ibadah is a collective term for everything which Allah loves and is pleased with from among the sayings and inward and outward actions." (Majmoo'ul-Fataawaa 10/149) Ibn al-Qayyim said: "Ibadah - Gratefulness to Him, Love of Him and Awe of Him." (Madaarij as-Saalikeen 1/74) Ibn Katheer said: "Ibadah in the language is humbleness (dhillah). It is sometimes said 'a levelled and smoothed road (mu'abbad) and an uneven road (ghair mu'abbad)' meaning (one has been) humbled, lowered, debased. Its usage in the Revelation: an expression of what brings together the perfection of Love, Fear and Hope (in Allah's service)." (Tafsir Ibn Kathir 1/25) Al-Qurtubi said: "The basis of Ibadah: humbling oneself (tadhallull) and submission (khudoo') and the duties of the Shari'ah are called 'Ibaadaat' because the servants adhere to them and perform them with submissiveness and out of humility to Allah the Exalted." (Al-Jaami' li-Ahkaamil-Qur'aan 1/225) Therefore, Ibadah means obedience with submission, and lowering one’s self, and accepting being led by Allah in everything He has ordered and everything He has forbidden. This is what the Messenger (saw) taught ‘Uday Ibnu Hatim (ra) as narrated by Imam Ahmed, Tirmidhi and Ibn Jareer: When ‘Uday Ibn Hatim heard of the call of the Messenger of Allah (saw), he fled to Al-Sham as he was a Christian before Islam. On the way, his sister, as well as a number of other members of his tribe, was taken captive. The Messenger of Allah then had mercy on her and let her go. When she returned to her brother, she persuaded him to consider Islam and meet the Messenger. ‘Uday was one of the leaders of his tribe, and his father, Hatim Al-Taa’i, was famous for his generosity. ‘Uday then proceeded to Medina and the people there began talking about his coming. When he met the Messenger, he was wearing a silver cross around his neck; the Messenger was reciting the verse "They took their Rabbis and Priests as lords besides Allah". When he heard this ‘Uday said: “They did not serve them”. He (the Messenger) replied: “Yes they did. They made what was Halal into Haram for them, and what was Haram into Halal for them, and the people followed them; that was their serving them”.