The Rebbe writes in a letter:
""From the time I was a child in school, and even before, a vision of the future exodus began to form in my mind:
A type of exodus in which the suffering of exile, mass persecution, and destruction will finally be understood.
And understood in the fullest sense, with a full heart, to the point that we can look back and say thank you God for everything we have been through.".
Igrot Kodesh, vol. 12, p. 414 (#4226). Written in 1956 to Yitzhak Ben-Zvi, then President of Israel.