Why Does Friar Lawrence in "Romeo and Juliet" Give Juliet the Potion?

Friar Lawrence gives Juliet the potion as part of his plan for Juliet and Romeo to reunite and as a way for Juliet to avoid going through with her wedding to Paris, according to About.com's Shakespeare section. Friar Lawrence wants to bring an end to the feud between the Capulets and Montagues and hopes that a union between Romeo and Juliet accomplishes this.