Vivekachudamani 16

medhavi puruso vidvanuhapohavicaksanah | 
adhikaryatmavidyayamuktalaksanalaksitah || 
(Sankaracarya's Vivekachudamani 16) 

One who has a keen memory and can argue for the scriptures and refute arguments against them, is fit for receiving Atma-vidya or the knowledge of the Self. 

False devotees think that studying books of the previous acaryas is unadvisable, like studying dry empiric philosophies. False devotees who have very little knowledge of such conclusions fail to achieve pure devotion for want of zeal in accepting the favorable directions for devotional service given by self-realized devotees. Such false devotees are like impersonalists, who alaaso consider devotional service no better than ordinary fruitive actions. 

There are certain necessary qualifications that must be present before any individuals or groups of individuals can actually participate in a debate. The necessary rules for a referee or arbitrator are also given and the necessary steps to be taken after the conclusion of a debate are also analyzed. 

There may be talks of philosophy, but if one party is defeated, the defeated person, he must be a disciple of the winning victorious party. But at the present moment, we'll go on talking for years together, and nobody is defeated; nobody is going to be a disciple. Then what is the use of talking like that. So this kind of things will not do. We have to follow the Vedic principle. 

A person who defends the Vedic knowledge is entitled to reach the Supreme Lord or he is a person who understands the science of self-realization.