Just a little fix to xander1981's code:
Code:
Sub LockNonactive()
    Dim nonAct As Range
    Dim CheckValue1 As String
    Dim CheckValue2 As String
    Dim cell As Range
    Set nonAct = ActiveSheet.Range("C3:C10")
    CheckValue1 = "Left"
    CheckValue2 = "Resigned"
    ActiveSheet.Unprotect
    For Each cell In nonAct
        cell.EntireRow.Locked = False
        If cell.Value = CheckValue1 Or cell.Value = CheckValue2 Then cell.EntireRow.Locked = True
    Next
    ActiveSheet.Protect
End Sub