One of the most famous mondegreens is the line Gladly the cross-eyed bear for - 'Gladly, the cross I'd bear'...a non conformist hymn.
Here are a few more religious ones:-
"Our Father who art in Heaven, Allah be Thy name..."
"...Blessed art thou, a monk swimming"
"..and lead us not into temptation but deliver us from eagle.."
"Mine eyes have seen the glory of the coming of the Lord he is trampling on the village where the great giraffe is stored..."
And from Newcastle "A wean in a manger..."
..."chased by an elephant" (Chaste and benevolent)
.."Let us praise the Lord in the words of the prairie tortoise"
Any further additions welcome......