My array keeps returning null even though there are objects in it when I NSLog it to the console. Any ideas?

I'm using the Parse query located in the Ribbit app to find messages that are sent to the current user of the app. I am not loading the messages into a tableview however. I want to do something else with them in another part of my code. Regardless, when I NSLog, my "self.messages" array within the block, it returns that there are messages that have been found, and loads them into the array. When I try accessing the self.messages array in another part of my code, however, it returns null. If someone has a solution that would be fantastic! I think it has to do with the asynchronous block call, but I don't know how to fix it. My code is below:

PFQuery *query = [PFQuery queryWithClassName:@"Messages"];
    [query whereKey:@"recipientIds" equalTo:[[PFUser currentUser] objectId]];
    [query orderByDescending:@"createdAt"];
    [query findObjectsInBackgroundWithBlock:^(NSArray *objects, NSError *error) {
        if (error) {
            NSLog(@"Error: %@ %@", error, [error userInfo]);
        }
        else {
            self.messages = objects;
            NSLog(@"Retrieved %d messages", [self.messages count]);
        }
    }];