Verified answer

He didn't.

He greatly increased both.

He emasculated the traditional nobility by building a palace at Versailles - outside of Paris,and thus away from the Paris mob who nobles might whip up to support them against the king - and moved his court there.This meant that the nobles had to go and live at Versailles if they wanted to have any contact with,and thus influence over,the king.This cost the nobles a lot of money and kept them away from their provincial estates,where they might meet out of the notice of the king and plot with others.

Louis created a new class of nobility (the Noblesse de la Robe) fronm the middle class and gave them all the ministerial jobs,so they ran the bureaucracy and the day-to-day government.Dependent on Louis for their jobs and titles,they were loyal to him,as were their underling bureaucrats in the provinces for the same reason.Previously,nobles in government positions had put loyalty to their class and traditional privileges before loyalty to the king;Louis effectively ended that system.

He also emlarged the army and used it for territorial expansion,using La Gloire in successful campaigns to distract the general population.

In 1685 Louis revoked the Edict of Nantes,which had allowed the French Protestant Huguenots freedom of worship and the right to maintain anumber of independent fortresses in France.After the revocation,Huguenots had to convert to Cathloicism or leave France.This meant that were going to be no more challenges to Royal authority from religious minorities within France itself,no more religious friction,and no more fortresses not controlled directly by the crown.

The cumulative effect of all this was to centralize all the political power in France under Louis' control - he greatly extended and legitimized the authority and legitimacy of the monarchy,neither were weakened at all during his long reign.