Leviticus 1: Wholly Sacrifices

“If your offering is a burnt offering from the herd, you shall make your offering a male without blemish. You shall bring it to the entrance of the Tent of Meeting, for acceptance in your behalf before God” (verse 3).
אִם־עֹלָה קָרְבָּנוֹ מִן־הַבָּקָר זָכָר תָּמִים יַקְרִיבֶנּוּ אֶל־פֶּתַח אֹהֶל מוֹעֵד יַקְרִיב אֹתוֹ לִרְצֹנוֹ לִפְנֵי ה׳׃
The Hebrew word for “without blemish” is תָּמִים (tamim). The word first appears early in Genesis describing Noah:
“This is the line of Noah.—Noah was a righteous man; he was without blemish in his age; Noah walked with God.—” (Genesis 6:9).
אֵלֶּה תּוֹלְדֹת נֹחַ נֹחַ אִישׁ צַדִּיק תָּמִים הָיָה בְּדֹרֹתָיו אֶת־הָאֱלֹהִים הִתְהַלֶּךְ־נֹחַ׃
First, on a more practical level, the Torah may be using the word for these sacrifices as Noah was the first person in the Bible to build and bring sacrifices on an altar:
“Then Noah built an altar to God and, taking of every pure animal and of every pure bird, he offered burnt offerings on the altar” (Genesis 8:20).
וַיִּבֶן נֹחַ מִזְבֵּחַ לַה׳ וַיִּקַּח מִכָּל־הַבְּהֵמָה הַטְּהוֹרָה וּמִכָּל־הָעוֹף הַטָּהוֹר וַיַּעַל עֹלֹת בַּמִּזְבֵּחַ׃
Even though he predates the Israelites by centuries, Noah set the standard for sacrificing pure animals and birds, just as God commands in this chapter.
Second on use of the word Tamim specifically, there is a famous dispute whether Noah was righteous and without blemish for his generation or was he independently righteous and without blemish. Perhaps God is presenting a similar quandary for the sacrifices themselves. Are the sacrifices the ultimate expression of holiness and connection with God or are they simply the right venue for the Israelites in that generation?
A note about the Sacrifices in general. The description of the sacrifices over the next several chapter is very detailed and the accompanying Gemara is even more detail oriented and often tedious every thought, action, and location is important and can throw the whole sacrifice into disarray. This begs the question, why does it matter. In Ancient Near Eastern Cultures like Mesopotamia (Sumerians, Babylonians, Assyrians): Sacrifices were common, often involving animals, grain, and drink offerings. Ritual texts like the Akkadian and Hittite cultic instructions describe procedures for offerings, purification, and temple service. These texts include details about which animals to use, how to prepare them, and which gods receive which offerings—but they are generally less systematic than Leviticus.
Ugaritic Texts (Canaanite religion): Describe offerings to Baal and other deities, including animal sacrifices and libations. Instructions exist, but they are more narrative and less legalistic than the Torah.
In Egyptian Ritual Manuals (e.g., Book of the Temple, Pyramid Texts, Coffin Texts): Prescribed sequences for offerings, purification, dressing the deity’s statue, and reciting hymns these included instructions on what foods, incense, and animals to present and emphasized ritual purity and correct performance, but not centralized laws for the entire population. Variations existed between temples and periods. In Greek Religion Sacrifices were central to Greek worship, especially animal sacrifices (thysia). There were norms: which animals suited which gods (e.g., white animals for Olympian gods, black for chthonic gods), how to burn portions, and who ate the meat. However, these were customary rather than codified laws. There was no single authoritative text like Leviticus; practices varied by city-state and occasion. Later Romans had highly structured rituals, especially in state religion. The pontifices and augurs maintained detailed calendars and ritual prescriptions. Texts like the Commentarii Pontificum and Fasti recorded sacrificial rules, but these were more about timing and priestly procedure than exhaustive legal codes. The ius sacrum (sacred law) existed, but it was not as comprehensive or centralized as biblical law.
Perhaps these detailed rules were another way to bring the Israelites at the time away from the more loose sacrificial rites that were prevalent in the ancient world. Much like the Mishkan, God is telling the people that if sacrificial worship is what they want, it must be done in a highly centralized, rules based, and specific way that God commands.