Kalev tried to quiet down the spies with their evil report with the words, טובה הארץ מאוד מאוד, that Eretz Yisrael is a very, very good land. The question asked was why "very very" and not just "very"?
There is an interesting Chassidic interpretation I heard from my good friend Rabbi Chaim Richman. The usage of this language of מאוד מאוד is also found in Pirkei Avot where it's written, הוי מאוד מאוד שפל רוח, "Be very, very humble."
The connection between the two מאוד מאוד's is the following: Only one who is exceedingly humble is able to fully appreciate the goodness of this land. His humility allows him to take in its beauty and holiness.
When one is haughty and arrogant, he is blinded and only focuses on superficialities and comforts. When comparing Israel with other places on a material level, Israel's uniqueness is not so apparent.
Being humble allows one's spiritual eyes to open and he realizes that there is no place on earth that compares with Israel, because it is a "very very" good land.