Mass. Gen. Laws ch. 239 § 11
Such stay shall be granted and continue effective only upon the condition that the applicant shall make a deposit in court of the entire amount, or such instalments thereof from time to time, as the court may direct, for the occupation of the premises for the period of the stay, at the rate to which he was liable as rent for the month immediately prior to the expiration of his term or tenancy plus such additional amount, if any, as the court may determine to be reasonable. The deposit shall also include all rent unpaid prior to the period of the stay. The amount of the deposit shall be determined by the court at the hearing upon the application for the stay, and such determination shall be final and conclusive in respect only to the amount of the deposit, and the amount thereof shall be paid into court, in such manner and in such instalments, if any, as the court may direct. A separate account shall be kept of the amount to the credit of each proceeding, and all such payments shall be deposited by the clerk of the court, and paid over to the landlord or his duly authorized agent, in accordance with the terms of the stay or the further order of the court.
Mass. Gen. Laws ch. 239, § 11