The literal meaning of Tauheed is to believe in the oneness and monotheism. In the terms of Sharia, Allah is believed to be one and unique in His attributes and perfections and to act according to His requirements, is called Tauheed. All beings are the creation of Allah Almighty and are acting according to His command. There is no God in the universe except Him. He is free from all defects and possessor of all perfections. He alone is worthy of worship. He is unique in His attributes and actions.
The first belief in Islamic beliefs is monotheism (Tauheed). From Hazrat Adam to Nabi Kareem Hazrat Muhammad (s), all the prophets who came to this world, they preached the Oneness of Allah Almighty. Without any belief in Tauheed and the lineage of Allah Almighty, one cannot enter the circle of Islam:
i. Importance of Monotheism (Tauheed) in Quran
The concept of Tauheed has been emphasized a lot in the Holy Quran. One of the Surahs of the Holy Quran is named 'Al-Ikhlas', in which Allah Almighty's oneness is defined. This surah says:
قُلْ هُوَ الله اَحَدُ اللهُ الصَّمَدُ لَمْ يَلِدْ وَلَمْ يُولَدْ وَلَمْ يَكُن لَّهُ كُفُوًا أَحَدٌ
Translation:
Say, "The truth is that Allah is One.
Tauheed holds the utmost priority in all the religious matters. Without belief in Tauheed, no worship and action is accepted. The most important right of Allah on His servants is to believe in His Oneness. Whoever adopts the belief of monotheism (Tauheed), Allah will save him from the fire of hell. The description of Tauheed belief is that Allah is recognized as One and Only in His Oneness, Divinity, and His Attributes.
ii. Types of Monotheism (Tauheed)
Tauheed-e-Rabviyat
Tauheed-e-Rabviyat is that man should have a firm belief that Allah alone is the creator and sustainer of everything and no one is his partner or companion in all this. Allah Almighty says:
الله الَّذِي خَلَقَكُمْ ثُمَّ رَزَقَكُمْ ثُمَّ يُمِيتُكُمْ ثُمَّ يُحْيِيكُمْ هَلْ
مِن شُرَكَابِكُمْ مَنْ تَفْعَلُ مِنْ ذَلِكُمْ مِنْ شَيْءٍ سُبْحَنَه وَتَعَلَى عَمَّا يُشْرِكُونَ
Translation:
"Allah is the One who created you, then gave sustenance to you, then He will make you dead, the He will make you alive. Is there any one from your (so- called) 'partners of God' who can do anything of that (kind)? Pure is He, and far higher than what they associate (with Him)." (Surah Ar-Rum: 40)
Tauheed-e-Alwahiyt
Tauheed-e-Al wahiyt means to believe that only Allah is the true deity and there is no partner in worshipping Him. It is absolutely not permissible to worship anyone else except Allah and then to spend the whole life according to the commandments of Allah. It is stated in the Holy Quran:
فَمَنْ كَانَ يَرْجُوا لِقَاءَ رَبِّهِ فَلْيَعْمَلْ عَمَلًا صَالِحًا وَلَا يُشْرِكْ بِعِبَادَةِ رَبِّةٍ أَحَدًان
Translation:
"So the one who hopes to meet his Lord must do righteous deed and must not associate anyone in the worship of his Lord." (Surah Al-Kahaf: 110)
Tauheed-e-Asma-o-Sifaat
Believing that Allah is one and only in His attributes and qualities, is known as Tauheed-e - Asma-o-Sifaat. Having the belief that just like Allah is unique and alone in all His attributes, same as He is in all His actions and deeds.
iii. Shirk and Its Types
who does not believe in the oneness of Allah, he commits shirk. Denial of A person monotheism (Tauheed) is polytheism (Shirk). The literal meaning of shirk is to make a partner or companion. Making someone a partner and sharer of Allah Almighty in divinity and His attributes is called shirk.
Shirk in Caste
This means that considering someone as the spouse and equal to Allah, or considering Allah Almighty as one's children, or considering someone as the children of Allah, it is called Shirk in the Self of Allah. Allah says:
لَمْ يَلِدُهُ وَلَمْ يُوْلَدُن
Translation:
"He neither begot anyone, nor was he begotten." (Surah Al-Ikhlas: 3)
Shirk in divinity
Associating the qualities of Allah with someone else or to consider someone else worthy of worship in divinity other than the Self of Allah, or associating with Allah, is Shirk. The requirement of the greatness of Allah is that only He should be worshipped. Allah has said in the Holy Quran:
اَلا تَعْبُدُوا إِلَّا إِيَّاهُ
Translation:
"That you worship none but Him"(Surah Bani Israel: 23)
Shirk in Attributes
Believing and relying in the nature and personality of someone other than Allah is called shirk in the attributes of Allah. Like, believing that someone has the vast knowledge, attributes or qualities like Allah is known as Shirk in attributes. Allah says:
لیس کمثله شی
Translation:
"Nothing is like Him (Allah)". (Surah Ash-Shura: 11)
All the creatures need Allah and all the qualities/attributes they possess are blessed to them by Allah whereas the attributes of Allah are His own and not granted by anyone else.
iv. Effects of Monotheism (Tauheed)