Isaac's name in Hebrew is Yitzchak, "he who will laugh."
Since he is never reported to have laughed, his name seems to be a contradiction to his personality.
But his name is directed to the future.
It says that Gevurah, which is now severity, will some day rise up and become greater even than Chesed.
Chesed is easy–for one who is all grace and love it is easy to be gracious and loving, but for Gevurah, who is awe and control and critical judgment, it is much more difficult, and so when it does happen, there will be laughter on earth as well as in heaven.
–Rabbi Adin Steinsaltz
From "The Many Sides of Chesed" in In the Beginning by Rabbi Adin Steinsaltz