Opinion by
Mr. Justice Williams,
The appellant is a son and heir at law of Alexander H. Miller, the testator. His father left an estate valued at about a half million of dollars. Six children survived him, five sons and one daughter. By his will he gave the bulk of his estate to one son, F. C. Miller, and made him one of his executoz'S. The appellant was practically disinherited. He came into the orphans’ court withizi the time allowed him by law, by petition asking leave to appeal from the decree of the register admitting the will to probate, and that an issue devisavit vel non be made up and certified to the court of comznon pleas of Allegheziy for trial. He alleged the znental incapacity of the testator to make a will at the time when the alleged will was executed; and he further alleged that undue influence had been exercised over *571the mind of the testator by F. C. Miller, the executor and devisee of nearly all of the testator’s fortune. A citation to the executors and heirs at law was duly issued and served, and appellant began the work of taking testimony preparatory to a hearing in the orphans’ court. While this was in progress the executors moved to dismiss the petition for reasons set up in their answer. This motion was heard and granted, and the petition was dismissed without any hearing upon the merits. This appeal was then taken to bring the decree so made, before this court for examination.
It is not denied that the petition was sufficient in form and substance, nor that it was presented within the time allowed by law, nor that proper parties were before the court to enable it to make a decree that should conclude all parties entitled to be heard. But the executors contended, and the orphans’ court held, that the appellant was estopped from contesting his father’s will upon twro grounds. These were, first, that his brother H. J. Miller had presented a similar petition a year or more before, which had been heard and dismissed by the orphans’ court; and that upon the hearing in that case A. H. Miller had been examined as a witness. For this reason the orphans’ court held him to be bound by the decree made in that case, although he had not been a party to it; and, second, that having received some small sums from the executors which the testator had directed should be paid to him, he had affirmed the will, and was estopped for that reason also from contesting it. We will consider these grounds for an estoppel very briefly, and in their order.
On turning to the record of the proceedings upon the petition of H. J. Miller, we find that the citation issued at his instance was served upon the executors only. No one of the heirs at law was brought in either as co-petitioner or respondent. The court had but two of the six children of the testator before it. This fact is conceded, in the opinion of the orphans’ court, delivered on the dismissal of the appellant’s petition in this case. The court said: “ The act of assembly and the rules of court requiring notice were not complied with ” upon the petition of H. J. Miller, but immediately added that such failure to comply with the law was “ only an error in procedure ” that did not affect the jurisdiction of the court or diminish the *572conclusiveness of the decree. Having thus settled the question of jurisdiction, the court brought the appellant into the case and held him concluded, not because he was a party or in privity with the parties, but because he was a witness and was examined as such. We cannot adopt either of these conclusions. The orphans’ court is not a common law court. It was created and its jurisdiction defined by the statutes of this state; and outside of the lines drawn for it it is without power, and its decrees are a nullity: Weyand v. Weller, 2 Gr. 103; Fretz’s Appeal, 4 W. & S. 433; Ake’s Appeal, 74 Pa. 116. With but two of the testator’s children before it, when a decree was made, it could not bind the four who had neither come in voluntarily nor been brought in by the citation. If it could not bind them, then it had no jurisdiction to settle finally the validity of the will at the stage of the proceedings then reached. It should have brought in all persons interested as heirs at law, devisees, or legatees, as well as the executors; and when all were on the record as appellants or appellees the orphans’ court could have proceeded intelligently to hear and determine the questions raised. The question asked by Nicodemus nearly nineteen hundred years ago, “Doth our law judge any man before it hear him ? ” admitted of but one answer then, or at any time since. The learned judge correctly described the failure to bring in the parties interested as an error in procedure ; but when a court of limited jurisdiction is pursuing a statutory proceeding, an error in procedure that is a violation of the statute, or that disregards the conditions on which its right to proceed rests, may leave the court without jurisdiction, and i ts acts eoram non judice. The suggestion that, being a witness, the' appellant is estopped from asserting that he was not a party to the appeal of his brother, is a clear mistake. There are some cases in which actual knowledge of the pendency of an action at law, or the existence of an incumbrance, or the like, may take the place of legal notice; but I know of no case where one who has been examined as a witness is, by reason of that fact alone, concluded by the judgment or decree rendered in the case. There must be other circumstances shown connect ing him directly with the litigation, as in fact a party to it, be fore he can be held bound by the result. Several cases have been cited in support of the general proposition that the appel*573lant and all the parties interested in the testator’s estate are bound by the decree dismissing the petition of H. J. Miller, but none of them come up to the question. Warfield v. Fox, 58 Pa. 382; Wilson v. Gaston, 92 Pa. 207, and Cochran v. Young, 104 Pa. 333, were actions of ejectment brought after the five years for appealing from the decree of probate had expired. They were attempts to impeach the decree of probate and the validity of the will in a collateral proceeding, which we said could not be done. What is said in these cases about the conclusiveness of the decree of probate, refers to the effect of such decree after five years have passed without an appeal from it. In Hegarty’s Appeal, 75 Pa. 503, the important question was whether the effect of the decree extended beyond the execution of the will and its authentication, as the last will and testament of the testator. It was there held that the decree settled two things, viz.: that the paper probated was the last will of the testator and that it was executed in accordance with the law. Other questions relating to its construction aqd legal effect were left to be settled when they should arise. It is well settled that in disposing of questions like that raised in this case, the orphans’ court exercises an equitable jurisdiction. It adopts the equity forms, and applies the rules and principles of equity. .The rule in equity requires all parties in interest to be made parties to the proceeding in which their interests may be affected, and if not brought in, a chancellor should dis miss the bill for want of proper parties: Gloninger v. Hazard, 42 Pa. 389; The Coal Company’s Appeal, 88 Pa. 499 ; Lance’s Appeal, 112 Pa. 456; Phila. v. River Front Railroad Co., 133 Pa. 134 ; Natural Gas Co. v. Douglass et al., 130 Pa. 283. We conclude therefore that the decree of dismissal in the proceeding begun by H. J. Miller was right, but that it should have been made for want of proper parties and for no other reason. It does not therefore stand in the way of the appellant in this ease or any other heir at law of the testator. It was not an adjudication upon the merits, for the court did not have the parties in interest before it, and was in no position to make a final decree.
The remaining question is over the effect of the receipt by the appellant of some small sums of money paid to him by the executors in compliance with the directions of the will. Is he *574estopped by tbe receipt of this money ? The general rule is that one who accepts a benefit under a will cannot deny the validity of that instrument. He cannot affirm the will so far as it is beneficial to himself and deny its validity as to others who are named as beneficiaries. Zimmerman v. Lebo, 151 Pa. 345. But an election in pais to take under a will should be intelligently made and should be unambiguous and positive in its character to amount to an estoppel. Dickinson v. Dickinson, 61 Pa. 401. Whether the receipt of money by a legatee claiming to be entitled to receive it, and much' more, as an heir at law, can be treated as an election to affirm the will, is, to say the least, very doubtful; but if, for the purposes of this case, we leave the conclusion reached by the court below on this question undisturbed, we do not think that the conduct of the appellant is of such a character as to amount to an irrevocable election to take under the will. The rule seems to be that a legatee who has received his legacy, and afterwards concludes to contest the will, may return the legacy to the executors and so relieve himself from the operation of the general rule that forbids him to take under the will that which testator gave him, and at the same time deny its validity as to others. The earliest case upon the subject appears to be Bell v. Armstrong, in 1 Addams, 365. In that case the next of kin had acquiesced in the probate of a will, and received a legacy under it. It was held that he was not estopped from contesting the will by the mere acceptance of the legacy, but that he might bring into court the money he had received and proceed with the contest. This case was followed by Braham v. Burchell, 3 Addams, 243, in which the contesting legatee was required to bring the legacy into court to abide the event of his contest. Hamblett v. Hamblett, 6 N. H. 333, was an appeal from a decree of probate by a legatee who had accepted the legacy. The proponent did not deny his right to appeal, but applied to the court for a rule on him to bring in the legacy before proceeding further to contest the will. The rule was granted and after hearing made absolute. The precise point does not seem to have arisen in this state. Cox et al. v. Rogers, 77 Pa. 160, was a case in which the legatee had received the benefit provided for her by the will, and had died without any effort to contest its validity. Her heirs at law sought to contest it. It was held that her accept*575anee and retention of the legacy estopped her and those claiming under her from denying the validity of the will. Wise v. Rhodes, 84 Pa. 402, involved substantially the same question. A married woman devised certain real estate to her sister on condition that she would take care of the husband of the testatrix, then an old and feeble man, and provide for him a comfortable maintenance during his natural life. After the death of testatrix, the devisee, at the request of the husband, took possession of the real estate, and assumed'the care and maintenance of the husband of her deceased sister. Several months later he changed his mind and desired to take against the will of his wife. He was held to be estopped under the circumstances of the case by his election and his enjoyment of the cave and maintenance provided for him. In both cases the rule laid down in Dickinson v. Dickinson, supra, was followed, and in Cox et al. v. Rogers it was restated thus: “ Such election to be binding must -be evidenced bjr unequivocal acts, clearly proved, must be made with a full knowledge of the facts, and the burden of showing this is upon him who alleges that an election has been made.” It would seem to be a fair deduction from our cases that where the acts set up are equivocal, or were done in ignorance of the rights of the doer, or where they consist merely of the receipt of a pecuniary legacy, and the money is returned before the appellant proceeds beyond the entry of his appeal, they will not amount to an estoppel.
The decree of the court below is reversed, and -the record is remitted with directions to the orphans’ court to proceed in accordance with this opinion.