It is a known fact that every language has one or more terms that are used in reference to God and sometimes to lesser deities. This is not the case with Allah. Allah is the personal name of the One true God. Nothing else can be called Allah. The term has no plural or gender. This shows its uniqueness when compared with the word god which can be made plural, gods, or feminine, goddess. It is interesting to notice that Allah is the personal name of God in Aramaic, the language of Jesus and a sister language of Arabic.
The One true God is a reflection of the unique concept that Islam associates with God. To a Muslim, Allah is the Almighty, Creator and Sustainer of the universe, Who is similar to nothing and nothing is comparable to Him. The Prophet Muhammad was asked by his contemporaries about Allah; the answer came directly from God Himself in the form of a short chapter of the Quran, which is considered the essence of the unity or the motto of monotheism. This is chapter 112 which reads:
"In the name of God, the Merciful, the Compassionate.
Say (O Muhammad) He is God the One God, the Everlasting Refuge, who has not begotten, nor has been begotten, and equal to Him is not anyone."
Some non-Muslims allege that God in Islam is a stern and cruel God who demands to be obeyed fully. He is not loving and kind. Nothing can be farther from truth than this allegation. It is enough to know that, with the exception of one, each of the 114 chapters of the Quran begins with the verse: "In the name of God, the Merciful, the Compassionate." In one of the sayings of Prophet Muhammad (PBUH) we are told that "God is more loving and kinder than a mother to her dear child."
But God is also Just. Hence evildoers and sinners must have their share of punishment and the virtuous, His bounties and favors. Actually God's attribute of Mercy has full manifestation in His attribute of Justice. People suffering throughout their lives for His sake and people oppressing and exploiting other people all their lives should not receive similar treatment from their Lord. Expecting similar treatment for them will amount to negating the very belief in the accountability of man in the Hereafter and thereby negating all the incentives for a moral and virtuous life in this world. The following Quranic verses are very clear and straightforward in this respect:
"Verily, for the Righteous are gardens of Delight, in the Presence of their Lord. Shall We then treat the people of Faith like the people of Sin? What is the matter with you? How judge you?" (68:34-36)