In the process of conversation, if a person often does this kind of action and picks up a cup to drink water, it first shows that he is thirsty when he speaks, and secondly, he may just want to control his emotions a little by drinking water. While drinking water, he wondered what you were talking about, and then how he would communicate with you.

Sometimes when we are talking, for example, when telling others what we will do, we will be nervous and always do some actions, so this is also one of his ways of speaking. After all, we didn't say we didn't respect you.