How do I use a variable for the result set field name in Microsoft Access VBA?

I want to use a variable to designate the field name. I need to do something like this:

 amt = rs![rst!job_cost_category]

Here is the rest of the code:  

Do While Not rs.EOF
        strSQL2 = "SELECT job_cost_category FROM job_cost_mapping"
        Set rst = db.OpenRecordset(strSQL2)
        Do While Not rst.EOF
            amt = rs![rst!job_cost_category]
            strSQL3 = "INSERT INTO tJobsAmtsAccts (LOC_NO,JOB,CATEGORY,AMOUNT)" & _
            " VALUES(" & Trim(rs!loc_no) & ",'" & Trim(rs!job) & "','" & rst!job_cost_category & "'," & amt & ")"
            DoCmd.RunSQL strSQL3
            rst.MoveNext
        Loop
        rst.Close
        rs.MoveNext
    Loop