List.First(List.Select()) comparing column table to containing table

background:

I have in my main table a CreateDate. I have created a column of data from the main table, for each row, it contains 1 or more records. I am trying to grab the First Date from the newtable where the CreateDate is < the current Records CreateDate.

Previosly, I was grabbing First record like so:

= Table.AddColumn(#"Merged Queries1", "StartDate", each List.First([NewTable][CreateDate]))

This grabs the CreateDate correctly, but just grabbign the 1st regardless.

I would like to change this to something like this:
= Table.AddColumn(#"Added Custom3", "StartDate2", each List.First( List.Select([NewTable][CreateDate], _ < [CreateDate] )))

I get the following error:
Expression.Error: We cannot apply operator > to types Record and DateTime.
Details:
    Operator=>
    Left=Record
    Right=1/12/2017 12:02:31 AM

Any ideas on how I can do this?

Sample Data:
CreateDate | Application | Severity | NewTable

1/12/2017 12:02:31 | TestApp | Info | <table>

<table> contents:
1/12/2017 12:01:00 | TestApp | Info

1/13/2017 12:01:00 | TestApp | Info

Thank you for any help

Joel