We’re told in John 8 that Jesus has gone “to the temple again” at dawn (v.2). By using the word “again,” John tells us this has become a regular event. A sizeable crowd expects this routine and now surrounds him, listening to him teach them.
We’re also told that Jesus sits down to teach (v.2).
At dawn [Jesus] went to the temple again, and all the people were coming to him. He sat down and began to teach them.
— John 8:2 CSB (emphasis mine)
In amongst the other information that verse 2 provides us with, Jesus' posture seems an irrelevant fact to most of us. But in a story that's all over within 11 verses and lacks narrative detail overall, the information we're given is important to our understanding.
And John wants us to know, Jesus is sitting.