5 But now I am going to the One who sent Me, and not one of you asks: “Where are you going?”
6 But because I have spoken these things to you your heart has been filled with grief.
It is sometimes said that it is not a good idea to go back to where you have come from. This may be true in some situations, especially if to go back is to return to old and outdated ways. However, there are times when it is good to go back, especially if this is what God requires of us.
To go back may mean repentance.
There was a time when Israel had sinned by abandoning God and worshiping the foreign gods of the other nations. Through the prophet Isaiah God spoke to the nation and said:
“Listen to me, all who hope for deliverance, all who seek the LORD! Consider the quarry from which you were mined, the rock from which you were cut!  Yes, think about your ancestors Abraham and Sarah, from whom you came. Abraham was alone when I called him. But when I blessed him, he became a great nation” – Isaiah 51.1-2 (NLT).
There was also a time when the prophet Elijah was told by God to go back:
Then the LORD told him, “Go back the way you came, and travel to the wilderness of Damascus. When you arrive there, anoint Hazael to be king of Aram – 1 Kings 19.15 (NLT). Elijah had fled from King Ahab and his Queen Jezebel. However, God met Him and told Him to return by the way he had come. This would not have been a comfortable return for Elijah.
Jesus told the disciples that the time had come for Him to return to where He had come from. He was about to return to the One who sent Him, the Father. We know that the way of His return was not easy, indeed it was the most difficult journey in the whole of history. His return to the Father was via the cross, on which He paid the greatest sacrifice that there has ever been, or ever will be.
In Revelation 2.5 the church at Ephesus was told to repent and return to the works they had done when they first believed:
Remember from where you have fallen, and repent and do the works you did at first, unless you should repent I will come and remove your lampstand from its place.
Any return to where we have previously been must only happen at the direction of the Holy Spirit.