Before 70 CE, avodah referred concretely to the daily and festival sacrificial rites priests performed in the Jerusalem Temple, the whole system of offerings, incense and prostration through which the Israelite people understood themselves to maintain their relationship with God at the one legitimate site of sacrifice. When the Second Temple was destroyed in the Roman suppression of the Jewish revolt, the sacrificial system it depended on ended with it, and rabbinic Judaism, developing in the following centuries, faced the question of what should stand in its place.
The rabbis' answer, articulated in the Mishnah and developed further in later halakhic literature, held that prayer could substitute for sacrifice, avodah she-balev, service of the heart, taking the place of avodah she-bakorbanot, service performed through offerings. Rather than abandon the concept of avodah altogether, the tradition preserved it in a new form: a fixed place within the daily and festival liturgy, and, on the single most solemn day of the year, an extended poetic recitation that keeps the memory of the Temple service specific and vivid rather than letting it fade into generalized regret. The same principle, that prayer stands in the place sacrifice once held, also shaped the daily Amidah, whose fixed hours of morning, afternoon and evening correspond to the Temple's own daily offerings, so that avodah as a category survived the Temple's loss not as a single substitute rite but as a governing idea running through the whole of subsequent Jewish liturgy.