Tawhid Al-Asma Was-Sifat.
(Maintaining the Unity of Allāh's Names and Attributes.)
Dr. Billal Philips
In the name of Allāh, the Most Gracious, the Most Merciful;
All the praise and thanks is due to Allāh, the Lord of al-`ālamīn. I testify that there is none worthy of worship except Allāh, and that Muhammad, Sallallāhu `alayhi wa sallam is His Messenger.
The Tawhid al-Asma was-Sifat has five main aspects:
1. In the Tawhid al-Asma was-Sifat, Allāh must be referred to according to how He and His Prophet (Sallallāhu `alayhi wasallam) have described Him without explaining away His names and attributes by giving them meanings other than their obvious meanings. Allāh in the Qur`an says He gets annoyed with the disbelievers and the hypocrites.
He says: "That He may punish the hypocrites, men and women, and the pagans’ men and women, who have an evil opinion of Allāh. A circle of evil is around them; Allāh is angry with them, curses them and has prepared for them an evil end." 
Thus, anger is one of God's attributes. It is incorrect to say that His anger must mean His punishment since anger is a sign of weakness in man and, as such, not befitting of Allāh. What Allāh has stated should be accepted with the qualification that His anger is not like human anger, based on Allāh's statement, "There is nothing like him" . The process of so-called "rational" interpretation when taken to its logical conclusion results in the denial of God's very existence. For, Allāh describes Himself as living and man lives, therefore, according to the rationalist argument; God is neither living nor existing. The fact is that the similarity between God's attributes and those of mankind is only in name and not in degree. When attributes are used in reference to God, they are to be taken in the absolute sense, free from human deficiencies.
2. Tawhid al-Asma was-Sifat involves only referring to Allāh as He has referred to Himself without giving Him any new names or attributes. For example, Allāh may not be given the name Al-Ghādib [the Angry one], in spite of the fact that He has said that He gets angry, because neither Allāh nor His messenger has used this name. This may seem to be a very fine point, but it must be maintained in order to prevent the false description of God. That is, finite man is in no position to define the infinite Lord of creation.
3. Allāh is referred to without giving Him the attributes of His creation. For example, it is claimed in the Bible and Torah that Allāh spent the first six days creating the universe then slept on the seventh.  For this reason, Jews and Christians take either Saturday or Sunday as a day of rest in which work is looked at as a sin. Such a claim assigns to God the attributes of His creation. It is man who tires after heavy work and needs sleep to recuperate.  Elsewhere in the Bible and Torah, God is portrayed as repenting for His bad thoughts in the same way that humans do when they realize their errors. Similarly the claim that God is a spirit or has a spirit completely ruins this area of Tawhid. Allāh does not refer to Himself as a spirit anywhere in the Qur'an nor does His Prophet (Sallallāhu `alayhi wasallam) express anything of that nature in Hadith. In fact, Allāh refers to the spirit as part of His creation. 
The key principle which should be followed when dealing with Allāh's attributes is the Qur`anic formula:
"There is nothing like Him and He is hearer and seer of all." 
The attributes of hearing and seeing are among human attributes, but when they are attributed to The Divine Being they are without comparison in their perfection. However, when these attributes are associated with men they necessitate ear and eye apparatuses which cannot be attributed to God. What man knows about the Creator is only what little He has revealed to him through His prophets. Therefore, man is obliged to stay within these narrow limits. When man gives free rein to his intellect in describing God, he is liable to fall into errors by assigning to Allāh the attributes of His creation.
In their love of pictorial representations, Christians have painted, carved and molded innumerable human likenesses and called them images of God. These have served to pave the way for the acceptance of Jesus' divinity among the masses. Once they accepted the conception of the Creator as being like a human being, accepting Jesus as God presented no real problem.
4. Tawhid al-Asma was-Sifat requires that man not be given the attributes of Allāh. For example, in the New Testament Paul takes the figure of Melchizedek, king of Salem, from the Torah (Genesis 14:18-20) and gives both him and Jesus the divine attribute of having no beginning or end:
"1. For this Melchizedek, king of Salem, priest of the highest God, met Abraham returning from the slaughter of the kings and blessed him, 2. And to him Abraham apportioned a tenth part of everything. He is first, by translation of his name, king of righteousness, and then he is also king of Salem, that is, king of peace.3. He is without father or mother or genealogy, and has neither beginning of days nor end of life, but resembling the son of God he continues a priest forever."  "4. So also Christ did not exalt himself to be made a high priest, but was appointed by him who said to him, 'Thou art my son, today I have begotten thee'; 5. As he says also in another place, 'Thou art a priest forever, after the order of Melchizedek'. 
Most Shi`ite sects [with the exception of the Zaidites of Yemen] have given their "Imāms" divine attributes of absolute infallibility,  knowledge of the past, the future and the unseen, the ability to change destiny  and control over the atoms of creation.  In so doing they set up rivals who share God's unique attributes and who, in fact, become gods besides Allāh.
5. Maintaining the unity of Allāh's names also means that Allāh's names in the definite form cannot be given to His creation unless preceded by the prefix ‘`Abd’ meaning "slave of" or "servant of'". Many of the Divine names in their indefinite form like Ra`uf and Rahim are allowable names for men because Allāh has used some of them in their indefinite forms to refer to the Prophet (Sallallāhu `alayhi wasallam):
"A messenger has come to you from among yourselves to whom anything which burdens you is grievous. He is full of concern for you and is full of pity [Ra`uf] and full of mercy [Rahim]". 
But ar-Ra`uf [the One Most Full of Pity] and ar-Rahim [the Most Merciful] can only be used to refer to men if they are preceded by `Abd as in `Abdur-Ra`uf or `Abdur-Rahim, since in the definite form they represent a level of perfection which only belongs to Allāh. Similarly, names like `Abdur-Rasul [slave of the messenger], `Abdun-Nabi [slave of the Prophet], `Abdul-Hussein [slave of Hussein], etc., where people name themselves slaves to other than Allāh are also forbidden. Based on this principle, the Prophet (Sallallāhu `alayhi wasallam) forbade Muslims from referring to those put under their charge as `Abdi [my slave] or Amati [my slave girl]. 
And Allāh Almighty knows best.
21. Surah Al-Fath, 48:6.
22. Surah Ash-Syura, 42:11.
23. Genesis 2:2, "And on the seventh day God finished his work which he had done, and he rested on the seventh day from all his work which he had done." [Holy Bible, Revised Standard Version [Nelson, 1951], p.2].
24. In contrast Allāh says explicitly in the Qur`an, "No tiredness overcomes Him nor sleeps..." [Surah Al-Baqarah 2:255].
25. Exodus 32:14, "And the Lord repented of the evil which he thought to do to his people." [Holy Bible, Revised Standard Version],
26. Allāh clearly states that in the following verse: "They ask you [Muhammad] about the spirit. Tell [them] that the spirit [exists] by my Lord's command" [Surah al-Isrā’ 17:85].
27. Surah Ash-Syura, 42-11.
28. Hebrews 7:1-3, [Holy Bible, Revised Standard Version].
29. Hebrews, 5:5-6, [Holy Bible, Revised Standard Version].
30. Muhammad Rida Al-Muzaffar states in his book Faith of Shi`ah Islam, [U.S.A.: Muhammadi Trust of Great Britain and Northern Ireland, 2nd ed. 1983]: "We believe that, like the prophet, an Imām must be Infallible, that is to say incapable of making errors or doing wrong, either Inwardly or outwardly, from his birth to his death, either intentionally or unintentionally, because the Imams are the preservers of Islam and it is under their protection." [p.32]. See also Islam, [Teheran: A Group of Muslim Brothers, 1973], p.35, by Sayyed Said Akhtar Rizvi.
31. AI-Muzaffar further states: "We maintain that the powers of the Imāms to receive inspiration has reached the highest degree of excellence, and we say that it is a divinely - given power. By this means the Imām is able to understand information about anything, anywhere, and at any time, and he understands by means of this Divinely - given power at once, without recourse to methodological reasoning or guidance from a teacher.
32. Al-Khomeini states: "Certainly the Imām has a dignified station, a lofty rank, a creational caliphate, and sovereignty and mastery over all atoms of creation." (Ayatollah Musavi Al-Khomeini, Al-Hukumah Al-Islamiyyah, [Beirut: At-Tale`ah Press; Arabic ed., 1979], p.52].
33. Surah At-Tawbah, 9:128.
34. Sunan Abu Dawud, [English Trans.], vol.3, pp. 1385-86, no.4957.