How important were Voltaire and the encyclopedia in the success of the Enlightenment?

Both Voltaire as an individual and the Encyclopedia as a collective text were crucial to the eventual success of the Enlightenment.
In Kant's famous essay, "Was Ist Aufklarung?" ("What is Enlightenment?") (1784) he argues that a central pillar of Enlightenment was man's liberation from his self-imposed infancy. Kant argued that to be Enlightened was to "dare to know" and to think for oneself, challenging the accepted dogmas of the world one lived in.
The Encyclopedia (or Encyclopédie as it was called in French) was a work devoted to this idea. This multi-volume text, edited and produced by Diderot and d'Alembert, was the first true encyclopedia of its kind, designed to help people acquire real knowledge for themselves. It featured articles on a wide range of topics, discussing everything from techniques and trades to abstract philosophical principles. It emphasized the importance of reason as a tool for achieving understanding, a key Enlightenment theme.
Similarly, Voltaire wrote many essays critiquing established orthodoxies, putting his own life at risk in challenging the power of the nobility and clergy. He was particularly compelled by the ideas of religious freedom and, even more pointedly, freedom from religion. This increasingly secular tone was also a key Enlightenment feature and Voltaire played a key role in popularizing it.