The earliest record of the blessing of oils seems while in the Apostolic Tradition, an early Christian document normally acknowledged to generally be dated before 235 CE. Now, consecrating the oils is carefully tied to preparation for Holy Saturday’s Easter Vigil, as 1000's are baptized into the Catholic Church https://liantong.com.tw/%e6%96%b0%e7%ab%b9%e6%88%bf%e5%b1%8b%e4%ba%8c%e8%83%8e%e8%b2%b8%e6%ac%be%e8%a9%b3%e7%b4%b0%e6%94%bb%e7%95%a5%ef%bc%9a%e6%8f%90%e4%be%9b%e8%b3%87%e9%87%91%e5%bd%88%e6%80%a7%e7%ae%a1%e7%90%86/