The advent of Islam also caused the relegation of the datuk to a medicine man, with traditional rice-planting ceremonies and other such remnants of traditional culture deemed incompatible with Islam. The 'pasusur begu', a ceremony invoking ancestors to aid the community, was also suppressed. Other aspects of adat were however tolerated, with the Mandailing Islamic ideology placing adat on the same level as Islamic law, as in contrast with the Minang practice of placing Islamic law above adat. In more recent times, learned Islamic scholars (ulama) studying abroad, have suggested that many traditional Mandailing practices, such as the 'Raja' hereditary leaders, were in conflict with Islam, being indicative of 'pele begu'. The Islamist ulama were in conflict for authority with the Namora-Natora, the traditional village legal practitioners, who were influenced by adat as much as Islam.