Stages and Limits of at-Tawhid

Source: The Learning of the Glorious Qur’an, by Ayatullah Misbah Yazdi page 44.

Believing in Allah's Oneness has many stages:
1. At-Tawhid in the Necessary Being, i.e. no being has come to existence by itself except Allah. In the terms of philosophy, it is the belief in a being whose existence is necessary. It is only Allah, the Exalted, whose existence is untrinsically a must, and from Whom the other beings take their existence.
2. At-Tawhid in creation. That is, there is no creator except Allah. This is a logical result of the previous point.
3. At-Tawhid in the genetic Lordship. The third stage of at-Tawhid is the genetic management and Lordship. That is, having admitted that Allah is the Creator of the world, we have to know who its manager and director is, and whether there is anyone, other than Allah, who manages the world without having to obtain His permission. Should there be an allegation that Allah had created the world, and then its management was handed over to some others, or Allah had nothing more to do with its management, or, if He had, He had it together with some partners, it would be multi-theism in Lordship or in Management. In this stage, a monotheist is that who believes that, as the creation of the world needed none other than Allah, similarly, the genetic management, directing and Lordship are exclusively Allah's.
4. At-Tawhid in the genetic Legislative Lordship. Having known that our Creator is Allah, and that our existence and management are exclusively in His hands, we have to believe also that none other than Him has the right to issue orders to us and to give law for us. Every law must be endorsed by the Divine order of permission before being regarded as authorized. Admitting that all existence is from Him, none shall have the right, without His permission, to command His creatures, to bid and forbid them, and to make laws for them. This is called "unity of Legislative Lordship."
5. At-Tawhid in worshipping. This is another stage of at-Tawhid. It is the unity of Divinity and worship. That is, none except Allah is worthy of being worshipped: " There is no god but Allah." This is also another outcome of that natural belief inherited in man. If our existence is from Allah, the management and directing our lives are up to Him. The independent effecter in the world is He, and the rights to legislate and issue orders are solely in His hands, there remains no room for anybody else to be worshipped. Him alone we must worship, which means we should place ourselves, unquestionably, at His service. This is what servitude to Him means. Only the one who owns everything deserves to be worshipped.
In other words, deity is a result of believing in His Lordship. Man worships the one whom he feels to have complete mastery and full command over him. So, the natural outcome of the genetic and Legislative Lordship of Allah is that no one else should be worshipped.
6. At-Tawhid in worshipping is another stage of at-Tawhid. It means that man should worship no one but Allah. The former stage was that there was no one deserving to be worshipped except Him. This stage requires that man should practically worship no one but Allah. This is called "unity of worshipping."
You might have realized that the Qur'an regards polytheism as a sin. When the grand sins are counted, "polytheism comes at the top of the list", as they say. This is worshipping, in practice, other than Allah, even if the worshipper did not believe that his worshipped one deserved worshipping, but he did it for some interests of his.
7. At-Tawhid in asking help is another phase of at-Tawhid. It means that man should practically seek the help of none other than Allah. Regarding Allah to be the real effective in the world means that no gain or loss affects us unless Allah wills it. So, how can we ask help from other than Him? Should we ask it from the one in whose hands is everything, or from the one who himself is in need of help, like ourselves? So, one of the aspects of monotheism is the unity of asking help: You do we worship and You do we seek for help [Suratul-Fatihah/4] This is a kind of unification. In case this aspect reaches its perfection, it will change into a psychological attribute, which, in the terms of the Islamic ethics, is called "Dependence on Allah". Many ayahs, after commanding people to worship Allah, order them to depend on Him: "...and on Allah should you rely if you are believers." [Suratul-Ma'idah/23]
8. At-Tawhid in fear. This is another aspect of monotheism. It means that man should fear none but Allah. Knowing that He is the real and only effective, why should we fear anyone else who can do nothing and is void of any power. All powers are originally from Him, while the others are no more than means of execution. The perfect monotheist is he who fears Allah alone, and no one else. Many ayahs enjoin: fear Allah, and fear none other than Him: " Those who convey the messages of Allah and fear Him, and do not fear any one but Allah..." [Saratul-Ahzab/39] and "...but do not fear them and fear Me if you are believers."[Surat 'Ali 'Im'ran/175]
9. At-Tawhid in hoping is another aspect of monotheism. It means that we should place our hopes in none other than Allah. This is also a logical consequence of believing in the Genetic Lordship of Allah. If we really believe that the real effective one in the world is Allah, why, then, shall we expect any thing from anyone else? No one else can do anything, so, all hopes must be confined to Him.
10. At-Tawhid in love is another aspect. If one believes that all perfections and beauties originally are Allah's, one's love originally belongs to Him, while other loves are false. Our love to somebody or something is naturally caused by the perfection or the beauty which we see in the beloved. Realizing that perfection or beauty is false, and that the one who has the original perfection and beauty is Allah alone, we should not, intrinsically, love anyone else.
The perfect monotheist is the one whose heart is given up to Allah, and, should he happen to love anyone else, it would be a radiation of his love to Allah and for His sake, as it is natural that when one loves somebody, his love covers his lover's belonging, too. If someone loves his friend he loves his clothes, his books and his house, too. Loving Allah, then, necessitates that whatever belongs to Allah is loved for that, too.
Finally, at-Tawhid reaches a stage where man becomes eyewitness of the fact that the entire existence and its affairs are in need of Allah, or, actually there is nothing but the need of Allah. In the terms of philosophy, this is expressed as: "The world of existence is the very connection, the very belonging itself, not something that belongs or has a connection." In an instance this subject appears in man in the form of a belief supported by proofs; in another instance, when man's knowledge increases and his faith becomes more perfect, it reaches a stage in which he becomes an "eyewitness" of this fact and understands it. These were the stages of monotheism (at-Tawhid).