2 Whosoever reflects thus is foolish, and without knowledge. When the dead were brought in, they were something; and when they were there for a long time, they became nothing. And, when the time shall have come that the dead shall rise, that nothing shall become something according to its former nature, and a change shall be added to its nature. O you unwise who reflectest thus, hear that which the blessed Apostle said when he was instructing a foolish man like you; for he said:— You fool, the seed which you sow unless it die is not quickened; and that which you sow is not like that which grows up into blade, but one bare grain of wheat or barley or some other seedling. And to each one of the seeds is given its own body. But God clothes your seed with its body as He wills.
Source: Demonstrations (New Advent)