Commentary for Kiddushin 68:9
אי הכי מצה והקהל נמי צריכי למאי צריכי בשלמא אי כתב רחמנא הקהל ולא כתב מצה ה"א נילף חמשה עשר חמשה עשר מחג הסוכות
While had the Divine Law written pilgrimage but not phylacteries, I would have reasoned, Let phylacteries be assimilated to mezuzah.<span class="x" onmousemove="('comment',' Since they are written together, and so women are liable to the former as to the latter.');"><sup>15</sup></span> Thus both are necessary.<span class="x" onmousemove="('comment',' The reason why two verses which teach the same thing cannot illumine other precepts is that if they were meant to do so one only would be sufficient, for the second could be deduced; and similarly all other precepts. But this obviously does not hold good when each is necessary in itself; in that case, therefore, both together throw light upon other cases.');"><sup>16</sup></span>
Daf Shevui to Kiddushin
Now stating that women are obligated in matzah is actually necessary, for if the Torah did not, I would have thought that just as they are exempt from sitting in the Sukkah which falls on the fifteenth, so too they are exempt from matzah, which also falls on the fifteenth.
But we do not really need the Torah to teach us that women are obligated to assemble. If children are obligated to assemble, as the Torah explicitly states, then obviously adult women are. Therefore, this verse is really not necessary.
And since it is not necessary, these two verses truly are “two verses that come as one.” The Torah could have stated the rule with regard to matzah and said nothing about assembling, and we would have known that women are obligated. And two verses that come as one do not aid in forming a general rule.