As we have learned, one of the central practices that must be done to meal offerings brought to the Temple is kemitza – when the kohen takes a fistful of the flour-oil-frankincense mixture – and places it in a keli sharet – one of the Temple vessels – as preparation for sacrifice on the altar. Kemitza has been described as one of the most difficult of the sacrificial services (see above, daf 11).
On today’s daf we find the opinion of Rabbi Ila who teaches that among the different meal offerings, it is the minḥat ḥotei – the sinner’s offering (when a person is obligated to bring a sacrifice for one of a number of specific sins, in the event that he cannot afford a more expensive sacrifice, he can bring a meal offering – see 5:1-13), that is truly the most difficult. This is because the minḥat ḥotei is ḥareiva – it is dry with no oil added to it, as was the case with other meal offerings (see 5:11). If the flour is entirely dry it is exceedingly difficult for the kohen to wipe away excess flour with his thumb and pinky, yet ensure that no additional flour will spill out, as well.
Rav Yitzḥak bar Avdimi apparently disagrees; he recommends adding water to the mixture and performing the kemitza in that manner. The Gemara concludes that their disagreement stems from the definition of ḥareiva. Rabbi Ila understands that it is entirely dry, with neither oil nor water; Rav Yitzḥak bar Avdimi understands that it cannot have oil added, but water would be permitted.
Although there are other meal offerings where oil is not added, e.g., the shtei ha-leḥem – the two loaves brought on Shavuot, celebrating the new wheat harvest (see 23:17) – nevertheless they are not considered to be ḥareiva, since they are kneaded with water. Furthermore there is no specific prohibition against adding oil to them as is the case in the minḥat ḥotei.