What is the meaning of an upside-down / inverted cross?

He was sentenced to be crucified, as the most severe and shameful death. But when he looked on the cross, he entreated the favour of the officers that he might not be crucified in the ordinary way, but that he might suffer with his head downwards: affirming that he was unworthy to suffer in the same posture as his blessed Lord and Master had done before him. His request being granted, he was crucified with his head downwards. Whether this be a fact or a mere legend, it well agrees with the fervent temperament and the deep humility of the great apostle.*

Peter certainly closed his life in martyrdom and by crucifixion; but whether, as alleged, he was crucified at Rome with his head downwards, there is very little evidence. He was most probably never at Rome at all; and that story of his leaving the city at the approach of danger, and meeting his divine Master going toward it, to Whom he addressed the enquiry, Domine, quo vadis? is neither true nor yet very well invented, albeit the words are written up on the Appian Way to this day.

Now there was one thing in which Peter had expressed his confidence — that is, to go to death or judgment or prison — anything for the Lord. Well now, the Lord takes this up. "Verily, verily, I say unto thee, When thou wast young, thou girdedst thyself, and walkedst whither thou wouldest; but when thou shalt be old, thou shalt stretch forth thy hands, and another shall gird thee, and carry thee whither thou wouldest not. This spake he, signifying by what death he should glorify God. And when he had spoken this, he saith unto him, Follow me."

Thus then, I think, we have the unspeakable grace of our Lord Jesus Christ meeting the desire of Peter's heart. He had done wonderful things for him already, when He committed what was most precious to the man that had failed so publicly and so repeatedly; but He goes farther. Had not Peter desired to follow the Lord to prison and to death? Certainly. "Well now," says the Lord, "I will give you all the desire of your heart." And look at the Lord's way! Look at the way of grace! When he was comparatively young he failed. When there was all the fervour and impetuosity, I must add, of his natural character, he completely broke down. The Lord puts no honour upon that; rather the contrary. He must bring it to nothing. It is what flesh would glory in. "But he that glorieth, let him glory in the Lord." And so the Lord gives him good ground for it, for He tells him, "When thou shalt be old, thou shalt stretch forth thy hands." It was not only that he was to die, but, "This spake he signifying by what death he should glorify God." Peter was to have his wish gratified to the very fullest. Peter was to suffer like his Master. I am not referring now to the tradition. I do not know whether there is any truth in his being crucified with his head downwards. Scripture says nothing of that kind. We are told so. It is a pretty story, and that is all one can say about it. It may be true; it is more likely to be false. You never can trust the stories of men in the things of God. I have never known a true story told by men in what concerns God, and where the spirit of man reigns. There is a fatality of error of the most extraordinary kind in the old ecclesiastical historians that touch upon these matters. Why, they cannot even tell correctly what is in the Bible, still less what is not. I say, therefore, that I do not believe that these stories are to be trusted. But this is to be trusted: he is to die like his Master, at any rate. He is to be crucified, so that the Lord would not only give him then to be led away a prisoner, but to suffer upon the cross. Peter would have what he desired, and more than he desired; but he would have it in pure grace; there was no strength, He would have it given him by the Lord; nay, farther than that, to "glorify God." No longer Peter's love; no longer glorifying Peter in any way. He that glorieth, let him glory in the Lord."

It was during the reign of Nero, the ravening "lion" (2 Tim. 4:17), that the Apostles Paul and Peter were martyred; the former by beheading, the latter by crucifixion, and, at his own request, with his head down as unworthy to die like his Master. We see no reason to doubt the traditions concerning these beloved Apostles; certain it is that both had special revelations of their near end, although not, perhaps, of the manner of their death. It may be well to remark in passing, that both Apostles firmly insisted on the saints rendering obedience and honour to Nero the Emperor — one of the worst and most cruel of men who ever sat on the throne of the Caesars; not the character of the ruler, but the office he fills, is that which demands the respect and reverence of the saints of God. (Rom. 13:1-7; 1 Peter 2:17.)

In the beginning of the Acts Peter's boldness in testimony is conspicuous. He was leaning on One stronger than himself and was carried on by the power of the Holy Spirit. He was miraculously delivered out of prison. The Lord had intimated to him that he would die the death of a martyr (John 21:19), and historians relate that he was crucified, and with his head downward by his own request: they also state that his wife died with him. He was the writer of the two epistles bearing his name.

Our Lord had said to him: "When thou shalt be old thou shalt stretch forth thy hands, and another shall gird thee, and carry thee whither thou wouldest not. This spake he, signifying by what death he should glorify God." (John 21:18-19.) It is agreed by all that he was crucified, and some add that he was crucified head downward at his own request, that he might not die like his Lord.