Come home. You have not found your happiness in foreign places and in alien forms that have no meaning to you, though you sought to make them meaningful. This world is not where you belong. You are a stranger here. But it is given you to find the means whereby the world no longer seems to be a prison house or jail for anyone. (ACIM:W-200.4)
And then there's the saying in Logion 86, another "prequel" to the New Testament (Mt. 8:20, Lk 9:58, and with apparent roots in the Q sayings collection also), which reads:
J said, "Foxes have their dens and birds have their nests, but human beings have no place to lay down and rest."The whole point then is that waking up, as Jesus in essence calls up on us to do, with his exhortations to "follow him" to a "Kingdom not of this world," means waking up first to the fact that this world is not our home, and that there must be "another way" to live. Simply put, as long as we think that our lives work, and are tolerable, we are not motivated to go look for an alternative, so Jesus always addresses the dissatisfaction with the ways of the earth in us with the assurance that there is indeed another way. He is not a new age guru who is interested in helping to make the world a better place. Once we commit to following him, the world does serve a purpose again:
Until forgiveness is complete, the world does have a purpose. It becomes the home in which forgiveness is born, and where it grows and becomes stronger and more all-embracing. Here is it nourished, for here it is needed. A gentle Savior, born where sin was made and guilt seemed real. Here is His home, for here there is need of Him indeed. He brings the ending of the world with Him. It is His Call God's teachers answer, turning to Him in silence to receive His Word. The world will end when all things in it have been rightly judged by His judgment. The world will end with the benediction of holiness upon it. When not one thought of sin remains, the world is over. It will not be destroyed nor attacked nor even touched. It will merely cease to seem to be. (ACIM:M-14.2)
In short the world is merely a perception problem of which we suffer as long as we mistakenly take the "tiny, mad idea" of the separation seriously, and it is our own discomfort in this dream existence, which inevitably wakes us up from it to the realization that this world is not our home and that we are finally willing to deal with, and reluctantly entertain, the possibility that Jesus was right and we were wrong. Jesus' teachings sound the sound of cognitive dissonance, to the point that wakes us up through the incongruities of our seeming experience, so he can lead us out of the desert of the ego, and back to the reality of Heaven.