OPINION OF THE COURT
POMEROY, Justice.Appellant, Harry Mimms was convicted in the trial court of carrying a concealed deadly weapon1 and unlawfully *556carrying a firearm without a license.2 The Superior Court affirmed the conviction, Commonwealth v. Mimms, 232 Pa.Super. 486, 335 A.2d 516 (1975), and we granted allocatur.
Our original decision was to reverse the Superior Court and direct a new trial on the ground that appellant’s revolver had been seized by the police in a manner which violated the Fourth Amendment to the Constitution of the United States. Commonwealth v. Mimms, 471 Pa. 546, 370 A.2d 1157 (1977). The Supreme Court of the United States granted the Commonwealth’s petition for certiorari, reversed our order and remanded the case to this Court for further proceedings.3 Having reexamined the record and the assignments of error not heretofore addressed,4 we determine that Mimms is entitled to a new trial on a ground other than the alleged search and seizure violation which formed the basis of our first decision.5
*557During the trial of appellant both Mimms and one Clayton Morrison, a passenger in Mimms’ automobile at the time of the arrest of Mimms, testified that it was Morrison who had brought the illegally possessed firearm into the ear.6 Morrison also testified that at the time of the seizure the gun was not located on appellant’s person but was concealed under the seat of the automobile. On cross-examination, the assistant district attorney asked Morrison the following questions and received the following answers:
“Q. Tell me, are you a good friend of Harry Mimms?
A. I am an acquaintance of him, I know him.
Q. You know him very well would you say?
A. Yes, sir.
Q. Arc you both Muslims?
A. Sir?
MR. ABRAMSEN: Objection, sir, I move for withdrawal of a juror.
THE COURT: Overruled.
BY MR. KLEIN:
Q. Are you both Muslims?
A. Yes, sir.
Q. In other words, when you say ‘Muslims, ’ followers of the Islam faith is that right?
A. Yes.
Q. Do you see Mr. Mimms often?
A. I see him frequently.
Q. How often?
A. Not that often I see him.
Q. How often?
A. Once or twice out of the day.
Q. Once or twice a day?
A. Yes, sir.
*558Q. Would you consider yourself a good friend of Mr. Mimms?
A. We are acquaintances.
Q. Quite good friends?
A. Yes, sir, I know him.
Q. Do you know his family?
A. No, I don’t.
MR. KLEIN: No further questions.” (Emphasis added.)
Questions relating to one’s religious beliefs are specifically forbidden by statute in this state. The Act of April 23, 1909, P.L. 140, § 3, 28 P.S. § 313 provides:
“No witness shall be questioned in any judicial proceeding, concerning his religious belief; nor shall any evidence be heard upon the subject, for the purpose of affecting either his competency or credibility.”
Although affiliation rather than belief was the thrust of the cross-examination above quoted, the one blends into the other. While circumstances can be imagined in which religious affiliation would be of relevance, it is clear from the present record that the religious affiliations of appellant and Morrison were irrelevant to any issue at trial and that such inquiry had not in any way been evoked by the direct examination of Morrison. Compare McKim v. Philadelphia Transit Company, 364 Pa. 237, 72 A.2d 122 (1950). The Commonwealth contends that the questioning was merely intended to show the friendly relationship between Morrison and Mimms and was not intended to capitalize upon the notoriety of the Muslim faith which obtains locally.7 The statute is, however, expressly worded to prevent the use of religious profession for the purpose of affecting credibility. If, as the Commonwealth argues, the questioning sought only to establish the friendship of the two men, there were *559numerous other ways, equally effective, to establish such a relationship without touching upon religion.
Appellant’s defense depended altogether on the credibility of the assertions by him and Morrison concerning the circumstances under which the search took place. Accordingly, the impeachment tactics that were employed by the prosecution in violation of an express act of legislature cannot, in the context of the present case, be considered harmless.8
Judgment of sentence reversed and a new trial ordered.
ROBERTS, J., filed a concurring opinion in which EAG-EN, C. J., and MANDERINO, J., join.. Act of June 24, 1939, P.L. 872, § 416, as amended 18 P.S. § 4416. That section has subsequently been replaced by §§ 907 and 908 of the Crimes Code. See the Act of December 6, 1972, P.L. 1482, No. 334, §§ 907, 908, 18 Pa.S.C.A. §§ 907, 908.
. Act of June 24, 1939, P.L. 872, § 628, as amended, 18 P.S. § 4628. That section has likewise been replaced by the Crimes Code, n. 1, supra. See 18 Pa.C.S.A. §§ 6101 through 6119.
. Pennsylvania v. Mimms, 434 U.S. 106, 98 S.Ct. 330, 54 L.Ed.2d 331 (1978). The opinion of the Court was unsigned. Dissenting opinions were filed by Mr. Justice Marshall and Mr. Justice Stevens (the latter opinion being joined by Mr. Justice Brennan and Mr. Justice Marshall).
. See Commonwealth v. Mimms, 471 Pa. 546, 548—49, n. 2, 370 A.2d 1157-58, n. 2 (1977).
The issue which we now hold compels reversal was considered by Mr. Justice Nix at the time of our original decision in this case and was the ground on which he would have ordered a new trial. Commonwealth v. Mimms, 471 Pa. at 553, 370 A.2d at 1161 (1977) (concurring opinion of Nix, J., joined by O’Brien, J.).
. The issue of the propriety of the search which produced the weapon from Mimms’ person after a police stop for a traffic violation was framed and argued to this Court on the basis of the Fourth Amendment of the Federal Constitution. This amendment was made applicable to the states in Mapp v. Ohio, 367 U.S. 643, 81 S.Ct. 1684, 6 L.Ed.2d 1081 (1961) and formed the basis of our earlier decision. It was not argued to us that such police activity as here occurred in relation to a routine traffic stop violated Art. I, Section VIII of the Pennsylvania Constitution and we do not address that question. To do so would be to violate the well-established and jurisprudentially sound rule that a court should not sua sponte raise an issue not properly placed before it by the litigants. See Reed v. Sloan, 475 Pa. *557570, n. 4, 381 A.2d 421, n. 4 (1977); Commonwealth v. Branham, 467 Pa. 605, 359 A.2d 766 (1976); Weigand v. Weigand, 461 Pa. 482, 337 A.2d 256 (1975).
. Prior to the trial in the case now before us, Morrison had pleaded guilty to the same charges for which Mimms was convicted.
. We cannot ignore the fact that Mimms and Morrison were black nor can we ignore the fact that certain adherents of the Muslim faith known as “Black Muslims” have been the subject of widespread unfavorable publicity, primarily because of involvement of some of its followers in criminal activity. See, e. g., Commonwealth v. Moody, 476 Pa. 223, 382 A.2d 442 (1977).
. We do not intend to establish a per se rule of reversible error in any case where a reference to religious beliefs occurs. Whether evidence, admitted in violation of a statute, actually deprives a defendant of his right to a fair trial must be viewed in light of the attendant circumstances. See Commonwealth v. Galloway, 476 Pa. 332, 382 A.2d 1196 (1978); Commonwealth v. Allen, 239 Pa.Super, 83, 361 A.2d 393 (1976).
In the present case, where the entire defense is predicated on the credibility of appellant and his witness, and where reference is made to a controversial religious organization in a manner which reflects not only on the witness but equally on the defendant, we cannot conclude that it is harmless.