You are to go down before me to Gilgal, and behold, I will come down to you to offer burnt offerings and to sacrifice sacrifices of peace offerings: you are to wait seven days until I come to you and show you what you are to do.”
“You are to go down before me to Gilgal.” This event was to occur at some point in the future, not immediately. It happened later (cp. 1 Sam. 13:7-13).