A dictionary of Proverbs (Oxford Paperback Reference)

The BLOOD of the martyrs is the seed of the Church
The Church has thrived on persecution. Cf. TERTULLIAN Apologeticus I. semen est sanguis Christianorum, the blood of Christians is seed.

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  1560 J. PILKINGTON Aggeus the Prophet U4V Cipriane wrytes that the bloud of Martirs is the seede of the Church. 1655 T. FULLER Church Hist. Britain I. iv. Of all Shires in England, Stafford-shire was.. the largest sown with the Seed of the Church, I mean, the bloud of primitive Martyrs. 1889 J. LUBBOCK Pleasures of Life II. xi. The Inquisition has even from its own point of view proved generally a failure. The blood of the martyrs is the seed of the Church. 1979 Church Times 15 June 10 It is not merely that ‘the blood of the martyrs is the seed of the Church’; it is that a little persecution is good for you. "adversity; Christianity
  

BLOOD will have blood
Violence begets violence. Cf. GENESIS ix. 6 (AV) Who so sheddeth man’s blood, by man shall his blood be shed.

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  a 1449 J. LYDGATE Minor Poems (EETS) 512 Blood will have wreche [vengeance], that wrongfully is spent. 1559 Mirror for Magistrates (1938) 99 Blood wyll haue blood, eyther fyrst or last. 1605-6 SHAKESPEARE Macbeth III. iv. 122 It will have blood; they say blood will have blood. 1805 SOUTHEY Madoc I. vii. Blood will have blood, revenge beget revenge. 1974 A. FOREST Cricket Term i. ‘Blood will have blood,’ quoted Lawrie smugly. ^revenge; violence
  

BLOOD will tell
Family characteristics or heredity cannot be concealed.

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  1850 G. H. BOKER World a Mask IV. in S. Bradley Glaucus (1940) 38 He looked like the tiger in the Zoological, when I punch him with my stick. .. Game to the backbone —blood will tell. 1914 WODEHOUSE Man upstairs & Other Stories 253 Blood will tell. Once a Pittsburgh millionaire, always a Pittsburgh millionaire. 2002 Oldie June 63 By the end, she herself has turned out to be the cousin of‘darling Clare’, and the daughter of long-lost Sir David Beaumont,.. which is a bit of a cheat really because blood will out, won’t it, and it’s not surprising that Daisy is such a marvel. "family