In the first place, we would like to stress that the Oneness of Allah is a rational truth, proved by the unity of the universe and its laws. The existence of various gods indicates non-unity in the system of the universe. Generally, the belief in the Oneness of Allah stipulates belief in the Oneness of His Soul, Attributes, and Deeds.
In this regard, we would like to cite for you the following: “The belief in the Oneness of Allah and His control of, and supremacy over, all the universe is an essential part of one’s faith. The Qur’an draws our attention to the world around us and invites us to contemplate on every aspect of creation. It tells us that there are pointers and indications in the universe which prove without any shadow of doubt, that there is no deity save Allah, the Creator of all. If we were to reflect on these, the only conclusion we would derive from them is that Allah is the Creator of all and the Lord of all. Such indicators are everywhere in the world, but we tend to overlook them because they are so familiar to us. If you consider how a big tree comes from a small seed and the process of planting the seed, its producing a shoot out of the soil, the way it establishes its roots, and how it grows, blooms and yields its specific brand of fruit, you will conclude that only Allah could have given the seed all these characteristics. But we do not tend to reflect on this, because the planting of trees and plants and waiting for their yield is so familiar to us that we tend to think of it as a simple natural process. It may be so, but who made it so natural? Similarly, the birth of every child is a miracle, but we tend to accept it as the most natural thing on earth. Such birth is certainly a natural phenomenon, but who said that natural phenomena are not miraculous? Since it is beyond man’s control, it is definitely subject to the will of a different power, i.e. that of Allah. Man has been studying this process of conception, pregnancy, and birth for centuries on end, but he still cannot influence, amend or change this process. Nor can man determine when to start it or influence its outcome. Not even the best techniques of helping women conceive change the fact that all efforts of man do not amount to more than inducing the start of the process and allowing it to take its course. Otherwise, can man conceive of any method which would bring children into being, without relying on the process of fertilizing a female egg with a male sperm?”
Moreover, “if a man dose not know that there is one and only one God Who is the Creator, the ruler, and the Sustainer of the universe and there is none else to share with Him even a shred of the Divine power and authority, he may fall a prey to false god’s and offer his homage to them solicit their favor. But if he knows the divine attribute of tawhid (Oneness of God), there is not the least possibility of his falling a prey to this illusion.
Similarly, if a man knows that God is omnipresent and omniscient and He sees, hears, and knows everything that we do in public or in private-nay, even our unexpressed thoughts!-then how can he afford to be indulgent and disobedient to God? He will feel that he is under eternal vigil and will, therefore, behave in the most appropriate way. But he who is not aware of these attributes of God may be misled, because of his ignorance, into God’s disobedience. So is the case with all other attributes of God. the fact is that the qualities and attributes which a man must possess, if he wants to pursue the way of Islam, can be cultivated and developed only out of profound knowledge of the attributes of God. It is the knowledge of God’s attributes, which purifies a man’s mind and soul, his beliefs, morals, and actions. And a mere cursory acquaintance with or just an academic knowledge of these attributes is not sufficient for the task ahead-there must be an unflinching conviction firmly rooted in the mind and heart of man so that he may remain immune from insidious doubts and perversions.”