This is the 8698th most frequent Russian word.
пасхального
"Easter" (adjective form, relating to Easter).
The word 'пасхального' here describes the context of the cake being related to Easter, functioning as an adjective modifying 'кулич'.
На столе стоит блюдо пасхального кулича.
There is a dish of Easter cake on the table.
In this sentence, 'пасхального' characterizes the hymn as being associated with Easter.
Мы слушаем пасхального гимн в храме.
We are listening to an Easter hymn in the church.
Here, 'пасхального' designates the holiday set as belonging to or themed around Easter.