Tertullian, Against Marcion 2.22
Therefore, in prohibiting the making of any likeness of things in heaven, on earth, or in the waters, He also reveals the reasons — those very substances that restrain idolatry — for He immediately adds: 'You shall not worship them nor serve them.' (Numbers 21:8-9) The bronze serpent, which the Lord later commanded Moses to make, did not fall under the heading of idolatry; it was a remedy for those being plagued by serpents. I pass over the figure of that remedy. Likewise, the golden Cherubim and Seraphim fashioned on the Ark were simply ornamentation, adapted to the Mercy Seat; they had causes far removed from the condition of idolatry on account of which a likeness is forbidden. They do not appear to violate the law against prohibited likenesses, because they were not caught in that state of likeness for which the likeness is prohibited.
We have spoken of the rational institution of sacrifices, which called people away from idols to perform duties for God. Had He rejected those duties again, saying, 'What is the multitude of your sacrifices to Me?' (Isaiah 1:11), He would have shown He never properly exacted them for Himself. For He says, 'I do not drink the blood of bulls,' since elsewhere He says, 'The eternal God neither hungers nor thirsts.' True, He accepted Abel's offerings and smelled Noah's burnt offerings with pleasure, but what was that pleasure — the flesh of sheep, the odor of burning victims? No: the simple, God-fearing heart of the offerers, which came from God, and the sweet fragrance of their intent, were reckoned as grace to God — not what was done as if He needed it, but the purpose for which it was done, namely, the honor of God. If a client offers a trifling gift to a rich man or king who desires nothing, does the gift's quantity and quality insult the recipient, or does the title of duty delight him? But if a client offers gifts, whether voluntarily or by the king's own decree, and observes the king's solemnities — yet without faith, without a pure heart, without full obedience in other respects — is it not inevitable that the king or rich man will cry out: 'What is the multitude of your gifts to me? I am full of your solemnities, your feast days, and your Sabbaths'? (Isaiah 1:13-14) They celebrated these according to their own desire, not the religion of God, making them their own, not God's. Therefore He demonstrated a conditional and rational rejection of the very rites He had prescribed to be administered.
Latin
Proinde et similitudinem uetans fieri omnium. quae in caelo et in terra et in aquis. ostendit et causas. [idolatriae scilicet substantiam cohibentes.] subicit enim: non adorabitis ea neque seruietis illis. serpentis autem aenei effigies postea praecepta Moysi a domino non ad idolatriae titulum pertinebat, sed ad remediandos eos, qui a serpentibus infestabantur. et taceo de figura remedii. sic et Cherubin et Seraphin aurea in arcae figuratum exemplum; certe simplex ornamentum. adcommodata suggestui, longe diuersas habendo causas ab idolatriae condicione, ob quam\' similitudo prohibetur, non uidentur similitudinum prohibitarum legi refragari, non in eo similitudinis statu deprehensa, ob quem similitudo prohibetur. diximus de sacrificiorum rationali institutione, auocante scilicet ab idolis ad deum officia ea, quae si rursus eiecerat dicens: quo mihi multitudinem sacrificiorum uestrorum? hoc ipsum uoluit intellegi, quod non sibi ea proprie exegisset. non enim bibam, inquit, sanguinem taurorum, quia et alibi ait: deus aeternus non esuriet nec sitiet. nam etsi ad oblationes Abelis aduertit et holocausta Noe odoratus est libenter, quae iocunditas siue uiscerum berbicinorum siue nidoris ardentium uictimarum? sed animus simplex et deum metuens offerentium ea, quae a deo habebant et pabuli et suauis olentiae, gratiae apud deum deputabatur, non. quae fiebant exigentem, sed illud, propter quod fiebant, ob honorem dei scilicet. si cliens diuiti aut regi nihil desideranti tamen aliquid uilissimi munusculi obtulerit, quantitas et qualitas muneris infuscabit diuitem et regem, an delectabit titulus officii? at si cliens ei munera (uel) ultro uel etiam indicta ordine suo offerat et sollemnia regis obseruet, non ex fide tamen nec corde puro nec pleno circa cetera quoque obsequio, nonne consequens, ut rex ille uel diues exclamet: quo mihi multitudinem munerum tuorum? *** plenus sum et sollemnitates et dies festos et uestra sabbata dicendo, quae secundum libidinem suam, non secundum religionem dei celebrando sua iam, non dei fecerant. condicionalem idcirco et rationalem demonstrauit recusationem eorum. % quae administranda praescripserat.