Well-known Toko Buku Wali Songo, a bookstore on Jalan Kwitang in central Jakarta, is piled to the ceiling with religious books. From the Quran and its translations to works on the Syariah (Islamic laws) and so forth, apart from the Islamic peripherals such as the sejadah (praying mat) and framed Quranic verses.

Also available in abundance are books on ilmu bathin (mystical powers), ilmu kebal (powers to become invincible), ilmu dalam (inner powers), ilmu ghaib (powers to become invisible) and other stuff including talismans.

The bookstore, in its confined space, has actually managed to make a strong representation of what and how Islam is practised in Indonesia, especially in the over-populated island of Java.

Call it co-existence, intertwining or complementary, Islam and mysticism in Indonesia are closely intertwined. The Indonesian Al-Ma'unah mahaguru (supreme teacher) Abbas Bakir sums it up quite well: "Venturing into mysticism, especially the ilmu dalam, further disciplined me as a Muslim. Prior to that, I sometimes missed my prayers and other religious requirements. However, when I started learning ilmu dalam, I had to perform all the religious obligations without fail if I wanted to be able to acquire the ilmu dalam. If I do not discipline myself in terms of performing my religious obligations, I will lose all my ilmu dalam."

It is as simple as that, and on that score, mysticism made Abbas, based on his contentions, a better Muslim. In short, mysticism provides, to a large degree, returns that can be of worldly use and not mere spiritual bliss and promises of heaven as accorded by observing the religious obligations.

Kiai (religious teacher) Abdullah Kassim of Cirebon said once a person took the path of tarikat (sufism), there could be no turning back because too much had been given to lose it for worldly temptations such as liquor, womanising, gambling or any other vices.

Despite all this, the problem that arises from Islamic mysticism is whether the path taken is truly according to the teachings of Islam, or ilmu sesat (deviating into black magic), which usually borders on cults and idolatry.

However, such concern is merely confined to Malaysia and not Indonesia as there is a stark difference between the two nations in terms of their practice and pursuit of Islam.

For better or worse, the way Islam is practised in Malaysia is streamlined, legislated and constitutionalised, making it difficult for anyone to just spread any teachings related to Islam without being scrutinised.

There is a standardised syllabus in religious studies in Malaysia and even those not attending recognised institutions are still required to follow the government syllabus.

In addition, the Malaysian religious authorities tend to conduct checks on any Islamic movements and if their teachings or practices are not in accordance with the official interpretation of Islam, they may end up being declared deviationists.

The thrust of all this legislation is the constitutional provision that Malays are automatically Muslims and it is illegal for them to change or give up the faith.

Such legislation is not prevalent in Indonesia. To the republic's authorities, the citizenry is allowed total freedom in their religious pursuits, deviant or otherwise, as long as they do not contravene the Undang-undang Dasar 1945 (UUD 1945 – the 1945 Indonesian Constitution), or the spirit of Pancasila which is akin to Malaysia's Rukunegara.

The Pancasila and UUD 1945 ensure that the nation remains a secular nation and this system of governance is strongly supported by all Indonesian leaders, including the present reformasi government. Against this backdrop, Islamic mysticism and sects whose teachings, like Shi'ism, are disallowed in Malaysia, flourish in Indonesia.

As such, it does not come as a surprise that movements like the Al Arqam – banned in Malaysia in 1994 – and several other outlawed tarikat groups, made their way to Indonesia and are actively reviving their programmes.

Apart from these groups, individual Malaysians too have crossed the waters to come to Indonesia to pursue religious studies and mysticism which are either not readily available or will never be able to be taught in Malaysia.

Leader of the Malaysian Al-Ma'unah group Mohd Amin Mohd Razali who was involved in the Sauk tragedy is but one person who had come to Indonesia to pursue Islam and mysticism. He was not the first nor will he be the last Malaysian to do so.

However, to be fair, although there is no legislation on Islamic studies or Islamic mysticism, there are pesantren (the equivalent of the Malaysian pondok) which have proven equal to, if not better than, that in Malaysia.

Yusuf Saad, 27, who hails from Pokok Sena, Kedah, who is in his fourth and final year in Islamic studies in Pesantren Suryalaya, Tasikmalaya in west Java, seemed to believe that there was nothing wrong with the place.

"In fact, there are things which it teaches here which prepares me to be better able to carry out the dakwah (missionary work). "My hope is that the Government will recognise my qualifications from here to allow me to teach when I go back home," said Yusuf, adding if that was not to be, he would then sit for another exam in Malaysia to obtain the recognition.

In Suryalaya, Yusuf admitted that apart from pursuing subjects like Quranic studies, the Hadith (prophetic tradition) and the Syariah (Islamic laws), he is also exposed to the tarikat.

While Yusuf took a direct path to Suryalaya and that is to pursue Islamic knowledge, his colleague, Razali Yahya, 40, from Tawau, Sabah, took a slightly meandering trail. An ex-addict who was hooked to drugs for 20 years, Razali said he came to know of Suryalaya after being treated in a Pondok Inabah (drug rehabilitation centre using Islamic spiritualism) in Sabah.

"From the teachers in Inabah, I came to understand that they were all graduates of Suryalaya and after I was completely healed of my addiction, I decided that I want to pursue the same tarikat. Once I have completed my studies in a couple of years, I want to return and offer my services to the Inabah and help others like me," he said.

Malaysia's education attache to Indonesia Abdul Rashid Samad seemed to have high regards for Suryalaya but expressed worries about Malaysians who did not register with the embassy when pursuing their religious studies in the republic.

While he was unwilling to give an estimate of how many unregistered Malaysians were studying in the pesantren, Abdul Rashid said it was difficult to keep track of them and admitted there were enough Malaysians studying in pesantren of doubtful reputation to cause concern. There are 1,720 Malaysians studying in Indonesia registered with the embassy.

While Abdul Rashid was being diplomatic and not prepared to reveal the extent of the problem, a Malaysian journalist based in Indonesia pointed out that Amin of the Sauk tragedy is merely the tip of the iceberg.

"There are a number of Malaysians who chose to study in some obscure Indonesian pesantren because it is cheap and provides a shortcut to acquiring the 'mystical powers'. They keep coming back for more and from what I gather, when they return to Malaysia, they start showing off their mystical prowess like Amin, convince others to be their students and encourage them to go to the same pesantren."

But Indonesia is not to be blamed for all this, as Islam and mysticism are a way of life and pursued by a cross-section of Indonesian society, from the president all the way down to the tukang becak (trishaw rider).

It is the Malaysians themselves, who came to these pesantren in Indonesia to pursue mysticism despite the stringent measures by the authorities to stop them. Amin and former Al Arqam members are probably youths who have been misled.

More of concern should be stories of some Malaysian leaders who are known to be paying thousands of ringgit to engage teachers in Indonesia who act as their spiritual advisers to ensure for themselves a "smooth" path up the political ladder.

They are wasting their money. At the Toko Buku Wali Songo, there are plenty of books on how to acquire "mystical powers". And they come cheap too – at RM4 a copy.