Let's talk about Calvary vs. cavalry, two words that sound similar and are close in their spellings but are two completely different things.
Calvary
Calvary is the name of the site of Jesus' crucifixion. It is the name of the hill outside of Jerusalem, also known as Golgotha. The word "Calvary" derives from the Latin word calvaria, which means "skull." The word "Golgotha" derives from the Aramaic word gulgulta, which translates to "place of the skull." The location is said to have been named after the skulls of criminals that were found there, and tradition links the location to Adam's skull.
An endless number of Christian songs and hymns mention Calvary. A couple of the oldest and most popular are "The Old Rugged Cross" and "Lead Me to Calvary." Famous gospel singer, the late Mahalia Jackson also recorded a song called "Calvary" multiple times over the course of her career.
Cavalry
Cavalry derives from the French cavalerie and the Italian cavallaria, but ultimately, both derive from the Latin caballus (horse) and caballarius (horseman). The term refers to soldiers, warriors, or other mounted troops fighting on horseback. The term is closely related to the word chivalry, which means "horse soldiery" or "knighthood" in Old French. The knighthood meaning is where the modern-day meaning of the word chivalry comes from, as it was used to describe the moral code of knights, which emphasized bravery, honor, courtesy, and loyalty.
These two words have very distinct meanings and are completely unrelated. Though they sound and are spelled similar, they are not interchangeable.