Going on pilgrimage to Abraham offers PF the most wonderful evangelistic possibilities.
Abraham was the Man of Sacrifice. When, like Mary, he accepted obediently the command of YHWH, he went from his own country and was first at Shechem, where "he built an altar to YHWH who had appeared to him". Between Bethel and Ai, "he built an altar to YHWH and called on the Name of YHWH". And, when he came and dwelt by the oaks of Mamre, which are at Hebron, he built an altar to YHWH. Then there was the mysterious Sacrifice of the Covenant, when the flaming torch passed between the sacrificial offerings. And his Offering made to the Divine Three. And the Sacrifice upon the Mount of Moriah, where, generations later, another Sacrifice was to be made, the Sacrifice which is at the centre of all places and of all times; the source of all Atonement; the Mercy Seat.
For a Bishop of Rome to stand in the land of Abraham and to summon all men and women to the one Sacrifice, to the one Faith, to the sacrificial outpoured Blood of the One Redeemer, would be a truly marvellous exercise of the Petrine Ministry. "Come to Jesus" would echo round the world and down the years.
In recent years, we have sometimes heard of "the Three Great Abrahamic Faiths". That is all nonsense. Or, if you dislike short words and sentences, I put it to you that, as a taxonomical exercise, it is unacceptable because, at least by implication, it has a strong momentum towards levelling (a factor which might not have been a matter of indifference to some of those who devised it and sponsor it). Of the three 'religions' which such people have in mind, only the one they call "Christianity" offers sacrifice to YHWH; a pure Offering; from the rising of the sun unto its setting. Rabbinic synagogue Judaism has known no sacrifice since the Fall of the Temple. Abraham would search in vain for an Altar of Sacrifice in any synagogie. Although, I believe, some vestiges of sacrificial activity survive in some parts of the Islamic world, no-one could say that Islam itself is a fundamentally sacrificial religion, so that in every mosque Abraham would recognise the Altar of Sacrifice at the heart of that worshipping community.
Abraham was and is our Patriarch. He sacrificed in the Faith he had been given, the Faith of the LORD who called him. His sacrifices pointed to (and are taken into) the One Sacrifice; the Oblation which the Lamb offers perpetually before His Father. To this immense and glorious Mystery all men and women are called.
I pray that God will preserve PF from the temptation to turn his Abrahamic Pilgrimage into some sort of syncretistic gesture towards our friends in 'other faiths'. I pray that he will turn from syncretism, because "Come to Jesus" would be a message heard by the simplest and by he most erudite. "Come to Jesus Now" would be a summons worth more than any number of carefully phrased ecumenical 'statements' for academics to study and argue over. Peter himself would be speaking. What better call could the vive-gerent of the Household of YHWH utter?
The Eternal Truth and the Spotless Sacrifice must not be cut down to being a mere Religion.
Even giving it a name ... "Christianity" ... risks turning it into one religion among others.
It is nothing of the sort.