When equity enforces specific reparation for the breach of a bilateral contract, the two sides of which constitute mutual and concurrent conditions, it encounters a difficulty of procedure which is unknown to courts of common law; for, as by the contract neither party is bound to trust the other, but each may insist that both shall perform at the same moment of time, and as equity enforces performance of the contract in every point except that of time, it follows that equity cannot enforce performance by the defendant unless the plaintiff also performs concurrently. If this were all, there would be no serious difficulty, so far as regards procedure; for then it would only be necessary for the court by its decree to appoint a time and place for performance by the defendant, and to direct him to perform, provided the plaintiff also performed. That, however, would be unjust to the defendant; for it would impose upon him the burden of making all the necessary preparations, and holding himself in readiness for performing his part of the contract, and yet leave him in a state of complete uncertainty, up to the last moment, as to whether the plaintiff would perform his part. Accordingly, equity says the plaintiff shall not be permitted to blow hot and cold, but that, having elected to have the terms of the contract carried out, notwithstanding the time stipulated for is past, he shall be bound by his election, and shall therefore be compelled to perform on his part. But how can performance be enforced against a plaintiff, against whom no complaint is made, nor any relief asked, and who would not be before the court at all, had he not come before it voluntarily, seeking relief against the defendant? The difficulty might perhaps be met by the defendant’s filing a cross-bill, praying that, if he be compelled to perform, the plaintiff also be compelled to perform concurrently with the defendant. But clearly the defendant is not bound to file a cross-bill; he does not wish to have the contract performed, and he is not bound to assist the plaintiff in his endeavors to compel the performance of it; nor will the defendant’s refusal to file a cross-bill justify the court in making a decree against the defendant which, but for such refusal, would be unjust. However, courts of equity have succeeded in surmounting this difficulty without any stretching of their powers, and without doing any injustice to either party; for they make it a condition of giving relief to the plaintiff that he shall submit to have a decree made against himself also, and indeed they treat a plaintiff as so
