Explain how Jonas's community is hypocritical.

Jonas's community is hypocritical in that it presents itself as a bastion of justice, even as it murders its most defenseless civilians. 
The idea behind "release" is to ensure that physical imperfections and spiritual infractions (which are said to lead to suffering, confusion, conflict, and war) are annihilated. To that end, Jonas' community consistently orders the release of the Old, rule-breakers, and even babies who fail to thrive (especially if they are the weaker of a set of twins). 
In the book, Jonas discovers the true meaning of "release" during his training to become the next Giver or Receiver of Memories. He is devastated when he discovers that his father has been cognizant of the meaning of "release" all along. 
While the Giver is allowed to lie (see Rule no. 8 in Chapter 9), others are supposedly prohibited from doing so. Yet, Jonas's father has obviously lied to Jonas by hiding the truth about "release" from his entire family and others in the community. So, this community is hypocritical because some of its most trusted members are willing to hide their most repugnant acts behind facades of righteousness. Meanwhile, others are more than willing to remain ignorant about the true nature of "release."