No man seweth a piece of new cloth—the Greek is ( ῥακους ἀγνάφου) undressed cloth, cloth newly woven, and before it has been dressed by the fuller—on an old garment. The latter part of this verse is better rendered, as in the Revised Version, thus: Else that which should fill it up taketh from it, the new from the old; and a worse rent is made.
The meaning of the words is this: An old garment, if it be torn, should be mended by a patch of old material; for if a patch of new material is used, its strength or fullness takes away from the old garment to which it is sewn; the old and the new do not agree, the new drags the old and tears it, and so a worse rent is made.