Many people feel it is sinful to celebrate Halloween. Some consider it to be Satan-worship.
These verses have to do with a little thing: a mustard seed.
2 Corinthians 6:14 – Do not be unequally yoked with unbelievers. For what partnership has righteousness with lawlessness? Or what fellowship has light with darkness?
2 Timothy 2:22 – So flee youthful passions and pursue righteousness, faith, love, and peace, along with those who call on the Lord from a pure heart.