“Soul! soul! for an apple or two; If you’ve got no apples, pears will do” is a chant that was used for souling on All Souls’ Day (November 2nd) in the 1800s.
   
Notes and Queries, on November 15, 1851, recorded this version from Shropshire, England:
     
“Soul! soul! for an apple or two;
If you’ve got no apples, pears will do.
Up with your kettle, and down with your pan;
Give me a good big one, and I’ll be gone.”
     
“Halloween apples!” is a related demand that has been used on Halloween, especially in Canada.
   
 
Wikipedia: All Souls’ Day
All Souls’ Day, also known as the Commemoration of All the Faithful Departed and the Day of the Dead, is a day of prayer and remembrance for the faithful departed, which is observed by Roman Catholics and other Christian denominations annually on 2 November. All Souls’ Day is often celebrated in Western Christianity; Saturday of Souls is a related tradition more frequently observed in Eastern Christianity. Adherents of All Souls’ Day traditions often remember deceased friends and relatives in various ways on the day. Through prayer, intercessions, alms and visits to cemeteries, people commemorate the poor souls in purgatory and gain them indulgences.     
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Popular customs
Many All Souls’ Day traditions are associated with popular notions about purgatory. Bell tolling is meant to comfort those being cleansed. Lighting candles serves to kindle a light for the poor souls languishing in the darkness. Soul cakes are given to children coming to sing or pray for the dead (cf. trick-or-treating), giving rise to the traditions of “going souling” and the baking of special types of bread or cakes (cf. Pão-por-Deus).
 
McClintock and Strong Biblical Cyclopedia
All-souls Day
All-Souls’ Day a festival held by Roman Catholics on the day after All-saints’ Day, for special prayer in behalf of the souls of all the faithful dead.
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In some parts of the west of England it is still “the custom for the village children to go round to all their neighbors souling, as they call it — collecting small contributions, and singing the following verses, taken down from two of the children themselves:
 
Soul! soul! for a soul-cake; Pray, good mistress, for a soul-cake, One for Peter, two for Paul, Three for Them who made us all.
 
Soul! soul! for an apple or two; If you’ve got no apples, pears will do, Up with your kettle, and down with your pan; Give me a good big one, and I’ll be gone.
 
Catholic Culture
Catholic Recipe: Soul Cakes III
The old English custom of “soul-caking,” or “souling,” originated in pre-Reformation days, when singers went about on All Saints’ Day and All Souls’ Day, November 1 and 2, to beg for cakes in remembrance of the dead. The “soulers,” as the singers were called, droned out their ditties repeatedly, tonelessly, without pause or variation.
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Soul cakes and souling customs vary from county to county, but souling practices always flourished best along the Welsh border. Even there, the custom is rapidly dying out. In hamlets of Shropshire and Cheshire, in parts of the Midlands, and Lancashire one sometimes hears the soulers chanting old rhymes such as:
 
Soul! Soul! for an apple or two! If you have no apples, pears will do. If you have no pears, money will do. If you have no money, God bless you!
   
Google Books
15 November 1851, Notes and Queries, pg. 381, col. 1:
Souling.—On the 2nd of November, All Souls’ Day, it is in Shropshire the custom for the village children to go round to all their neighbours souling, as they call it, collecting small contributions, and singing the following verses, which I took down from tow of the children themselves:—
 
Soul! soul! for a soul-cake;
Pray, good mistress, for a soul-cake.
One for Peter, two for Paul,
Three for Them who made us all.
 
Soul! soul! for an apple or two;
If you’ve got no apples, pears will do.
Up with your kettle, and down with your pan;
Give me a good big one, and I’ll be gone.
 
Soul! soul! for a soul-cake;
Pray, good mistress, a soul-cake, &c.
 
An apple or pear, a plum or a cherry,
Is a very good thing to make us merry.
Soul! soul! &c.
 
Th soul-cake referred to in the verses is a sort of bun, which until lately it was an almost general custom for persons to make, and to give one another on the 2nd of November. Perhaps some of your readers can state whether this custom prevails in other counties in England. It seems to be a remnant of the practice of collecting alms, to be applied to the benefit of the souls of the departed, for which special masses and services were formerly sung on All Souls’ Day.
W. FRASER.
 
Google Books
Barthomley:
In letters from a former rector to his eldest son
By The Rev. Edward Hinchliffee
London, UK: Longman, Brown, Green and Longmans
1856
Pg. 143:
The song of the children was short and to the point:—
Pg. 144
“Soul, soul, for an apple or two,
If you have no apples, pears will do;
Pray, good mistress, a soul-cake?”
 
Newspapers.com
16 June 1856, Aris’s Birmingham Gazette (Birmingham, UK), pg. 2, col. 2:
ALL SOULS’S DAY (N. and Q., 85). W. A. L. will find the customs usual to this day explained in Brand’s “Popular Antiquities,” in the notes to “All Hallow even.” I took down the following from the recitation of a little boy a few years ago at Upton Magna, Salop. It is evidently imperfect. I may observe that it is generally believed to be the remains of the old custom of begging money to be applied for the purpose of procuring masses for the souls of the dead:—
 
“Soul! Soul! for an apple for two;
If you’ve got no apples, pears will do.
One for Peter, two for Paul,
Three for Him who made us all.
Up with the kettle, down with your pan,
Give me an apple and I’ll be gone.”
 
At Eccleshall, Staffordshire, the children go a “Souling” on this ay, collecting fruit, cakes, &c., repeating the following rhyme, which differs somewhat from the one used in Shropshire:—
 
“Soul! Soul! for a Soul cake,
Pray you good Mistress for a Soul cake.
Soul! Soul! for an apple or two,
If you’ve got no apples, pears will do;
A plum, or a cherry,
Or anything else; that will make us merry.
Up with the kettle, and down with your pan,
Give me an apple and I’ll be gone.”
 
On the even of this day the farm labourers dress themselves in their best clothes, and visit the different farm houses, singing songs. They are afterwards regaled with ale, &c. The “Souler’s” song, sung on All Soul’s eve in Cheshire, is given in Ormerod’s History of that County, vol. I, p. III.—J. G. B.
 
Newspapers.com
25 January 1858, Aris’s Birmingham Gazette (Birmingham, UK), “Soul Cakes,” pg. 1, col. 4:
Early on All Souls’ morning, the ears of the dwellers in villages were regaled with the following persuasive ditty, melodiously chanted by women and children of the neighbourhood:—
 
“Soul, soul, for an apple or two!
If you’ve got no apples, pears will do;
An apple, a pear, a plum, or a cherry,
or any good thing to make us merry;
One for Peter, two for Paul,
Three for Him that made us all!”
 
Newspapers.com
4 November 1880, The Bossier Banner (Bellevue, LA), “All Saints and All Soul’s Days,” pg. 3, col. 2:
In some parts of the West of England it is customary for the children to go around to all the neighbors on this day, souling, as they call it—collecting small contributions, and singing the following verses:
 
Soull! Soul! for a soul cake,
Pray, good mistress, for a soul cake.
One for Peter, two for Paul,’
Three for them who made us all.
Soul! Soul! for an apple or two;
If you’ve got no apple, pears will do.
Up with your kettle, and down with your pan;
Give me a good big one, and I’ll be gone.
 
The soul cake referred to in the verse is a sort of bun, which formerly, it was an almost general custom, in England for the people to make, and give to one another on November second.