וַיִּשְׁלַ֗ח אֶֽת־נַעֲרֵי֙ בְּנֵ֣י יִשְׂרָאֵ֔ל וַיַּֽעֲל֖וּ עֹלֹ֑ת וַֽיִּזְבְּח֞וּ זְבָחִ֧ים שְׁלָמִ֛ים לַיהוָ֖ה פָּרִֽים׃
I posłał młodzieńców z synów Israela i ofiarowali całopalenia i zarzynali ofiary opłatne Wiekuistemu, - woły.
Mishneh Torah, Forbidden Intercourse
Immersion was in the desert before receiving the Torah, as is said, "Sanctify yourselves today and tomorrow; wash your clothes." The offering, as is said, "Send the young ones of Israel to bring elevation offerings" - and everyone in Israel brought them.