In Daniel 10:3, Daniel refrains from anointing during his fast of mourning — opposite to Jesus' instruction here to anoint as normal to avoid appearing to fast.

Ecclesiastes 9:8 links oil on the head with joy — the very reason Jesus tells fasting disciples to anoint: to appear joyful, not sorrowful.

In Luke 7:46, Jesus rebukes Simon for not anointing his head — showing this was a customary act, which explains why Jesus tells disciples to do it during fasting.