The letter "p" with a cross through it, specifically the Greek letter rho (Ρ) with a cross superimposed, is a symbol known as the
Chi-Rho (☧). It's one of the earliest and most common Christograms (a monogram or combination of letters that forms an abbreviation for the name of Jesus Christ).
Here's what it represents in Christianity:
* Christ: The Chi-Rho combines the first two letters (Χ and Ρ) of the Greek word "Χριστός" (Christos), which means "Christ" or "Anointed One."
* Jesus Christ: By extension, it represents Jesus Christ himself.
* Victory: It has also been seen as a symbol of Christ's victory over death and evil, especially after its use by Emperor Constantine I.
* Association with Constantine: Emperor Constantine I, before a pivotal battle, had a vision of the Chi-Rho and instructed his soldiers to put it on their shields. He won the battle, and subsequently, the Chi-Rho became associated with Christian victory and imperial authority.
In summary, the Chi-Rho is a visual shorthand for Christ, and it signifies his presence, his victory, and the Christian faith.