Every line above is reproduced from the holding institution’s own catalogue entry, which is linked. Where their title, date or attribution differs from ours, theirs is the one printed here.
The halo does not make this a sacrifice. The binding does.
Every lamb Zurbarán painted is a merino, and this one lies with its legs tied. Of its own version the Prado notes an animal still alive, in a posture unmistakably sacrificial and reminiscent of famous images of martyred saints.
Here Zurbarán paints a nimbus, which for Miguel Ángel Aparicio sharpens the icon's symbolic meaning, and the words TANQUAM AGNUS. They are not the Baptist's Behold the Lamb of God; Aparicio traces them to Isaiah: dumb before his shearer, he shall not open his mouth.
Sources: San Diego Museum of Art, Spanish Art page, entry for Agnus Dei, 1947.36 · San Diego Museum of Art, Mission & History · Museo Nacional del Prado, collection entry for A lamb (Agnus Dei), Francisco de Zurbarán, P007293 · Miguel Ángel Aparicio Tovar, 'El ganado ovino en la obra de Zurbarán', X Congreso Nacional, IV Iberoamericano y I Hispanoluso de Historia de la Veterinaria, Olivenza 2004, pp. 99-104, at p. 102 · Isaias 53:7, Douay-Rheims (Challoner) · John 1:29, Douay-Rheims (Challoner)
The next day, John saw Jesus coming to him; and he saith: Behold the Lamb of God. Behold him who taketh away the sin of the world.
John 1:29 · Douay-Rheims (Challoner), from the project’s own corpus at data/bible_drc.js
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