The ruins of the Abbey church of Einsham. 1657
source: Eynsham online
The maxim spare the rod and spoil the child (in which and implies a consequence) means that if children are not physically punished when they do wrong their personal development will suffer.
In one of his homilies, Ælfric of Eynsham (circa 950-circa 1010), Benedictine abbot of Eynsham and scholar, wrote:
(edited and translated by Benjamin Thorpe, published in London in 1846)
Godes wisdom sæ᷇de, þurh Salomones muð, “Styr ðinum cilde, and sleh hit mid gyrde, and ðu swa alyst his sawle fram deaðe. Se ðe sparað his gyrde, he hatað his cild; and se ðe hit lufað, he᷇ lærð hit anrædlice.”
God’s wisdom said, through the mouth of Solomon, “Correct thy child and strike it with the rod, and thou so shalt redeem his soul from death. He who spareth his rod hateth his child; and he who loveth it, teacheth it soundly.”
Ælfric of Eynsham was referring to the Book of Proverbs, a book of the Bible containing maxims attributed mainly to Solomon. In the Early Version (around 1382) of the Wycliffe Bible, Proverbs, 13:24, is:
Who spareth to the ȝerde¹, hatith his sone; who forsothe looueth hym, bisili² techeth.
¹ ȝerde = yard (cf. gyrde in Ælfric’s homily): a stick or rod used as an instrument for administering strokes by way of punishment
² bisili: busily
Proverbs, 13:24, is as follows in the King James Version (1611):
He that spareth his rod, hateth his sonne: but he that loueth him, chasteneth him betimes.
In the New International Version (2011), this verse is:
Whoever spares the rod hates their children,
but the one who loves their children is careful to discipline them.
In Magnyfycence. A goodly interlude and a mery deuysed and made by mayster Skelton poet laureate late deceasyd (first published circa 1529-30), the English poet John Skelton (circa 1460-1529) wrote:
There is nothynge that more dyspleaseth god
Than from theyr chyldren to spare the rod
The current form of the phrase is first found in Hudibras: the second part (London, 1664), by the English poet Samuel Butler (died 1680):
If Matrimony and Hanging go
By Dest’ny, why not Whipping too?
What med’cine else can cure the fits
Of Lovers when they lose their Wits?
Love is a Boy, by Poets styl’d,
Then Spare the Rod, and spill³ the Child.
³ The verb spoil has taken the place of spill in this sense.
The equivalent French maxim is qui aime bien châtie bien, the one who loves well chastises well, a rendering of Latin qui bene amat bene castigat. These phrases correspond to the second half of Proverbs, 13:24, “the one who loves their children is careful to discipline them”.