As a Paladin Cassy gains her strength from a pure heart, a strong will and an unbreakable faith in the five gods of Tyria. Cassandra worships all of them more or less...
Balthazar - The god of war and fire is the god Cassandra addresses in her prayers directly. She asks him for guidance and strength in battle. Balthazar favors her strength and grants her his blessing.
Dwayna - The goddess of life and air is the second most important god for Cassandra. She asks Dwayna for protection.
Lyssa - The goddess of beauty and illusion favors Cassandra a lot, even though Cassandra doesn't seem to worship her explicitly.
Melandru - The goddess of nature and earth is basically unimportant for Cassandra. As a faithful believer in the five gods she offers Melandru her prayers frequently.
Grenth - The god of death and ice. Cassandra despises him for taking her father before his time. She accepts the fact that all life must end and she asks Grenth to guide the souls of the fallen to the place of eternal rest.

Prayer of War
Balthazar guide my arm and be my strength
Dwayna bless my armor and my heart
Lyssa distract my foes
Melandru drink their blood
Grenth be swift and quick
For I will strike my foes with cold steel
For I will bring judgement over them
So be it until my last breath
In your name
Amen

Prayer of Redemption
Spiritus Dominatus - Domine libra nos.
From the lightning and the tempest - our gods deliver us
From the plague, deceit, temptation and war - our gods deliver us.
From the scourge of the charr - our gods deliver us.
From the blasphemy of the fallen - our gods deliver us.
From the curse of the undead - our gods deliver us.
A morte perpetua - Domine libra nos.

Devout Ejaculation
Domine fac ut eos neco antequam me necant.

Convent of Holy Wrath Creed
A blessing for the living
A flower for the dead
With the sword of justice
A punishment of death to evil doers
This is how we will arrive at the altar of the saints
This I swear
In the name of the five gods