Massachusetts General Laws Part III. Courts, Judicial Officers and Proceedings in Civil Cases (Ch. 211-262) Ch. 253, § 16

The execution issued on such judgment, if not otherwise satisfied, may, within thirty days after judgment, be levied on the land so subject to the lien; and the officer may thereupon sell, in the manner provided for the sale of land on execution, such land or so much thereof as is necessary to satisfy the execution and the expenses of the levy. Such sale shall be valid against any claim which has accrued within the time covered by the lien.