When Reb Chaim Moshe Alperovitch came to the Rebbe for the first time, he was asked to speak at the Tzach convention in 770. When a report of the speech was brought to the Rebbe, the Rebbe’s face glowed with satisfaction.
In 5716 (1956), when Reb Chaim Moshe came to the Rebbe for the first time, he was asked to speak at the Tzeirei Chabad convention in 770. He began by listing various levels of yiras Hashem (fear of G-d) as they are explained in Chassidus, and went on to expound on their merits.
Suddenly he cried out, “The Rebbe has discussed in the latest maamar the concern of timtum hamoach and timtum halev (intellectual dullness and emotional apathy). Fellow chassidim! We must overcome these obstructions, and clean our minds and hearts!”
When a report of the speeches at the convention were brought to the Rebbe, the Rebbe’s face glowed with satisfaction with Reb Chaim Moshe’s speech, truly spoken from the heart.
(Otzar Hachassidus EY page 419)