Answer
Barlaam, a Calabrian monk and scholar, was the first opponent in Palamas' major theological controversies. These controversies, which took place in the 14th century, centered on the nature of divine light and the role of human beings in attaining salvation. Barlaam argued that divine light was created, while Palamas maintained that it was uncreated and could be experienced by those who had attained a high level of spiritual perfection.