The earliest record on the blessing of oils seems in the Apostolic Tradition, an early Christian document generally acknowledged to generally be dated prior to 235 CE. Currently, consecrating the oils is carefully tied to planning 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/