Thompson, Ch. J.
delivered the opinion of the court.
This case comes before the court on a bill of exceptions taken at the trial. It was an action of covenant, to recover five hundred dollars, as stipulated damages agreed on between the parties, to secure the performance of certain covenants contained in an agreement of the 25th of November, 1815. There was no question upon the trial, but that it *203was a case of stipulated damages. The agreement, with respect to that, is too explicit to admit of any doubt. The parties bound themselves to each other in the sum of five hundred dollars, which, in the language of the covenant, they consented to fix and liquidate as the amount of damages to be paid by the failing party, for his non-performance, to the other. The evidence, as appearing on the bill of exceptions, shows that the plaintiff was always ready, and did every thing on his part required by the agreement; and that the defendant did not and could not perform, on his part, by reason of certain incumbrances on the land which he had covenanted to convey to the plaintiff.
The only question upon the trial was, whether the plaintiff had not waived the stipulated damages, by the indulgence he had given to the defendant. By the covenant, it appears that the deed was to be given by the first day of January next after the date of the agreement. The evidence shows, that the defendant, finding some difficulty in having the necessary survey made in season, his surveyor had a conversation with the plaintiff on the subject, when the plaintiff1 said, that it was immaterial as to the day ; that if the defendant performed his contract, he would take no advantage, on account of his not doing it on the precise day mentioned in the agreement. No advantage was taken; for the plaintiff was always willing to accept the deed, and perform, on his part. But the defendant was unable to comply with his covenant, and convey'the land, free from incumbrances. He comes now, with a very ill grace, to set up this indulgence given him, to discharge himself from his covenant. It is a sound principle, that he who prevents a thing being done, shall not avail himself of the nonperformance he has occasioned. So that if, by the covenant, any act was to have been done by the plaintiff, before the conveyance was to be made, the defendant’s conduct would have dispensed with the performance. But no such act was required. We have no oyer of the covenant, but, according to the declaration, the covenants were independent, or, at all events, nothing is required to be done by the plaintiff, until the delivery of the deed. He has averred his readiness to perform on his part, and this is fully shown bv *204the proof. Even admitting that an agreement to extend the time of performance would be a waiver of the stipulated damages, there was not, in fact, any such agreement. Nothing ever passed between the parties on the subject.. All that the plaintiff ever said, as to the extension of the term, was, that if the defendant would perform his contract, he would take no advantage of its not being done on the precise day. This could not be called an agreement to extend the time; no day was fixed, to which the performance was postponed, and it would be a violent and unnatural construction of the plaintiff’s conduct, to consider it as intended to waive his covenant, and enter into a new agreement, especially ás such paroi agreement would be void under the statute of frauds. If this is to be considered a new agreement, which in any manner affects the covenant, the plaintiff’s whole remedy is gone. He can no more sustain an action for his real damages to be proved, than he can for the stipulated damages; and this was not pretended on the trial. An agreement, absolutely void, can never be considered as altering, revoking, or modifying a valid contract. In all the cases referred to, where the term has, been extended, the subject matter was such, as might be embraced by a paroi agreement, and the parties have been driven to the new contract for redress; but when the new contract is void in law, and the party without remedy if turned over to it, it would be extremely unjust. Nor was it contended on the trial, that the plaintiff’s remedy was on the new agreement. That forms no part of the objection to the recovery, as stated in the bill of exceptions. It is placed entirely on the ground that an extension of the time is a waiver of the stipulated damages only. But the mere extension of the time of performance is not a waiver of any thing. This principle is settled by the case of Evans v. Thompson, (5 East, 193.) where it was held, that the. time for making the award being enlarged by agreement, did not dispense with the stipulation t.o make the submission a rule of court. The court said, the agreement to enlarge the time must be understood as by reference virtually incorporating in itself all the antecedent agreement between *205the parties, relative to that subject, as if the same had been formally set forth and repeated therein. In every point of view, therefore, in which this case can he viewed, the plaintiff is clearly entitled to judgment.
Judgment for the plaintiff.