Alternatively, use CFQueryParam and get rid of the DateFormat() calls:
<cfquery name="getdevotional" datasource="#application.database#">
SELECT display_date, title
FROM mobile
where display_date BETWEEN <cfqueryparam value ="#mydatetime#" cfsqltype="cf_sql_date"> AND <cfqueryparam value="#DateAdd('d', 30, mydatetime)#" cfsqltype="cf_sql_date">
</cfquery>
-Carl V.
