Well, I already had written some points about "Wadat-ul-Wajood" in some other threads. Below I am compiling them with necessary modifications for the purpose of this thread:

Wahdat-ul-Wajood:

'Wahdat-ul-Wajood' in Islam is an ideology, which tends to equate God and the Universe, in essence. The meaning of 'Wahdat-ul-Wajood' is that 'wajood' (i.e. existence) is only one (i.e. there is wahdat in wjaood). All the multiple things visible and observable to us are just deceptions. In somewhat detail, the non-living matter, living things, spirits, soul and intellect etc. all have been emanated from God in the same way as Light emanates from sun. In other words, The universe as a whole is a reflection of God Himself. The reflection of God cannot be considered to be any separate entity whose existence can be thought of as something separate from God Himself. So according to this creed, God and Universe are essentially one and the same thing.

The meaning of 'Wahdat-ul-Wajood' can be explained by differentiating the concepts of 'mono-theism' and 'monism'. 'Mono-theism' is the same thing to the concept of 'Islamic Tauheed'. As distinguished from 'monism', this view asserts that there is permanent distinction and separation between God and the Universe. God existed when universe had no existence. Existence of God is eternal whereas that of universe is temporal. Universe is not the reflection of God Himself. God is the Creator who created this universe out of nothing. So there cannot be any unity between God and universe.

‘Monism’ on the other hand, seems very similar to ‘wahdat-ul-wajood’, as this ideology also emphasizes on ‘oneness’ of God and universe. Islamic concept of ‘oneness’ is very much different to the ‘monistic’ idea of ‘oneness’. Islamic ‘oneness’ says that God is one. That one God has created universe. There are no other gods. The ‘monistic’ oneness does not say that God is only one. It actually says that there is complete oneness in the God and universe. Monism thus does not make any separation like that of creator and creature between God and the universe. This ‘oneness’ gives the same meaning as ‘wahdat’ in the ideology of ‘wahdat-ul-wajood’.

So this ‘wahdat-ul-wajood’ says that reality is a single unity. If there is no difference between God and universe, then essentially there is also no difference between creator and creature. Creatures are the reflections of God Himself. If all the creatures are the reflections of a single entity then there should be no difference in the status of different creatures. All humans, irrespective of their religion, ethnicity and nationality are the reflections of one single entity, so they all are equal in their status. Thus the result of universal brotherhood ultimately results from the ideology of ‘wahdat-ul-wajood’.

There are many other distinguished aspects of this ideology also. The objective before humans, according to this ideology is to push back the individual personality in an endeavor to reach at a stage, in the process of spiritual development, where in spiritual terms, the deception of plural existence becomes clear and the individual ultimately ends up (‘Fana-Fi-Allah’) in the single real entity, which is God.

Many elements of Wahdat-ul-Wajood Philosophy can be traced back to Greek Mysticism particulary to the 1st century AD Philosophy or Theology of Neo-Platonism as well as to ancient Indian Vadentas. Below I am highlighting the influence of Neo-Platonism Philosophy on this 'Wahdat-ul-Wajood':

The main doctrine of 'Neo-Platonism':

This theology, or philosophy, was developed by the 1st century A.D philosopher Platinus. According to him, the whole reality or the source of origin of everything is a single unity which he calls 'Zat-e-Behet'. This entity, according to him, transcends the universe but everything of the universe which are (i) First Intellect, (ii) Ruh-e-Kul, (iii) Ruh-e-Alvi of humans, (iv) Ruh-e-Safli of humans and (v) matter; have been EMANATED from that 'zat-e-behet'. 'Emanation' means just like light emits from sun in such way that no loss is suffered by the sun.

According to the details, first of all 'first intellect' emanated directly from 'zat-e-behet'. Then Ruh-e-Kul emanated from the intellect. Then Ruh-e-Alvi of humans emanated from that Ruh-e-Kul. Then this Ruh-e-Alvi lost its true status and became inclined to matter and thus became 'Ruh-e-Safli'. According to Platinus, human body is composed of matter. Human soul has been imprisoned in matter in this way. The highest goal before human is to try to purify his soul (through 'riazat', 'maraqba' etc. etc.) so that the soul may get freedom from the imprisonment in matter. After getting freedom from matter, the 'purified' soul then starts backward, or better to say, up-ward movement towards Ruh-e-Kul, then to intellect and finally again units with the 'zat-e-behet'.

Platinus says that when human soul is in imprisonment of matter, it feels intense missing of 'zat-e-behet' and the soul acquirs the feeling of 'Be-Qarari' for meeting or uniting with 'zat-e-behet'. This feeling of 'Be-Qarari' of human soul for uniting with 'zat-e-Behet' has been named as 'Ishq' by Platinus.

It is this 'Ishq' which compells humans to do such things as 'maraqbas', 'riazat' etc. etc. so that the soul may be purified and get freedom from the imprisonment of matter. To get his soul re-united with the zat-e-behet is the unltimate real goal for any human, according to this doctrine.

It is important to mention that not only Muslim Sufis, but Muslim rationalist philosophers such as Al-Farabi and Ibn-e-Sina also had adopted this emanation doctrine with its details --- but after some modifications. Muslim Sufis have derived their concepts of 'Ishq-Haqiqi', 'Fana-Fi-Allah', etc. from this doctrine. In addition, various concepts which are found in works of Muslim scholars such as sufli, alvi, first intellect etc. also have Greek origins. Just like in this 'Neo-Platonism', where ultimate goal for human is to get his soul re-united with 'zat-e-behet', in many forms of Sufism, the ultimate goal before Sufi is also 'Fana-fi-Allah. Just like in Neo-Platonism, where maraqbas and riazats are required for this purpose, in many forms of Sufism also the same maraqbas and riazats are required for this purpose. In addition, according to Neo-Platonism, since everything has been emanated from a single source, so all the beauty found in universe is just the reflection of that singe source. This concept has been taken up by Sufis by the name of 'Husn-e-Azal' and they have named the 'attraction' for this 'Husn-e-Azal' as Ishq.

Hazrat Muhayyudin Ibn-e-Arabi, the main proponent of Islamic Wahdat-ul-Wajood, has taken many things from Neo-Platonic doctrines. Both 'Neo-Platonism' and Ibn-e-Arabi's 'Wahdat-ul-Wajood' are 'monistic' doctrines instead of 'mono-theistic' doctrines. Monism asserts the unity between God and universe. In other words, according to Monism, God and Universe are one and single thing as no other thing can exist except God. Mono-theism (Islamic Tauheed) on the other hand, asserts that God and universe are two separate entities. The thing which mono-theism emphasizes is that God is only one i.e. there are not more than one gods. But fact remains that one God is considered separate entity than universe. Universe is the creature and the creator is only one God, according to Mono-theism. Secondly Ibn-e-Arabi has described 'creation' of universe in Neo-Platonic terminology of emanation etc. In addition, he also has adopted another Greek concept of 'Logos', after some modifications.

Regards!

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