i'm a klutz

I'm sure this can be done better. Thisdate is a set of dates in, say a1 to a100. in b1 to b100 there are values [the val range]. I'm trying to return the value in val that corresponds to thisdate matching startdate.

this code produces an error.

   Function INIT(THISDATE As Range, STARTDATE As Date, VAL As Range)
   Dim C, B
   Dim ICOUNT As Integer, MAX As Integer
   Dim ARR1()
   Dim ARR2()
    MAX = THISDATE.Count
    ReDim ARR1(1 To MAX)
    ReDim ARR2(1 To MAX)
    
   ARR1 = Array(THISDATE)
   ARR2 = Array(VAL)
   For ICOUNT = 1 To MAX
    If DateValue(ARR1(ICOUNT)) = STARTDATE Then
        INIT = ARR2(ICOUNT)
        Exit Function
        End If
        Next ICOUNT
   End Function