You don’t HAVE to but we highly recommend it when possible as it engages more of your senses, which makes the processes more effective by engaging more of your brain and nervous system in the process. For limiting beliefs that are deeply rooted or carry a strong charge, some people even like to say them with emphasis or even yell them. What’s most important is the intention (i.e. for them to be cleared or programmed in) and doing the practices consistently. However, saying the clearing and programming statements out loud can increase the effectiveness noticeably, which is why we recommend it.