[1.] The reason, O children greatly beloved, why we entertain you portion by portion with the thoughts taken from the Scriptures, and do not at once pour all forth to you, is, that the retaining what is successively set before you may be easy. For even in building, one who before the first stones are settled lays on others, constructs a rotten wall altogether, and easily thrown down: while one who waits that the mortar may first get hard, and so adds what remains little by little, finishes the whole house firmly, and makes it strong, not one to last for a short time, or easily to fall to pieces. These builders we imitate, and in like manner build up your souls. For we fear lest, while the first foundation is but newly laid, the addition of the succeeding speculations may do harm to the former, through the insufficiency of the intellect to contain them all at once.