אִשֶּׁה (isheh) is the Hebrew term for the fire-offering: any sacrifice that ascends to YHWH on the altar through fire. It is the broadest sacrificial category in Leviticus — the burnt offering, the grain offering, the peace offering, and the sin offering can all be described as isheh. The defining feature is the fire: the offering goes up (olah, from the same root as ascension) to YHWH through the medium of flame, and the result is the reach nichoach (pleasing/soothing aroma) that YHWH accepts.
Leviticus 1:9 gives isheh its paradigmatic form: 'and the priest shall wash its entrails and its legs with water. And the priest shall burn all of it on the altar as a burnt offering (olah), a fire-offering (isheh), a pleasing aroma (reach nichoach) to YHWH.' The three-term description — olah + isheh + reach nichoach — is the Levitical grammar of accepted sacrifice: the upward-going (olah), the fire-medium (isheh), and the divine reception (reach nichoach). All three together describe the complete act of sacrificial communion with YHWH.
Leviticus 9:24 gives isheh its YHWH-kindled form: 'And fire came out from before YHWH and consumed the burnt offering and the fat portions on the altar, and when all the people saw it, they shouted and fell on their faces.' The fire for the first offering at the Tabernacle comes from YHWH himself: he lights the altar. Thereafter the priests are commanded to keep this fire burning continually (Lev 6:13: 'fire shall be kept burning on the altar continually; it shall not go out'). The isheh at the altar is YHWH's own fire, maintained by the priests — the fire does not belong to the worshiper; it belongs to YHWH.
Numbers 28:3-4 gives isheh its daily-tamid form: 'This is the fire-offering (isheh) that you shall offer to YHWH: two male lambs a year old without blemish, day by day, as a continual burnt offering (olat tamid). One lamb you shall offer in the morning and the other lamb you shall offer at twilight.' The tamid-isheh is the daily covenant-maintenance sacrifice: two lambs, every day, morning and evening, on YHWH's altar. The tamid-isheh is Israel's acknowledgment that the covenant requires daily renewal — the fire never goes out, the offering never ceases, the reach nichoach rises to YHWH continuously.
Leviticus 10:1-2 gives isheh its judgment form: 'Now Nadab and Abihu, the sons of Aaron, each took his censer and put fire in it and laid incense on it and offered unauthorized fire (esh zarah, strange fire) before YHWH, which he had not commanded them. And fire came out from before YHWH and consumed them, and they died before YHWH.' The esh-zarah (H784+H2114) of Nadab and Abihu is the counter-isheh: fire offered to YHWH that YHWH did not authorize. The same fire that lit the altar in Leviticus 9:24 (divine acceptance) consumes the sons in Leviticus 10:2 (divine judgment). The isheh-fire is holy — approach it rightly, and it becomes reach nichoach; approach it wrongly, and it consumes.
For the preacher, אִשֶּׁה (isheh) gives the congregation the grammar of approach to a holy God: every isheh declares that access to YHWH comes through substitution, fire, and the mediation of the priestly system — pointing forward to the one offering that ends all offerings.