Code in my model is validates :place_id, :title, :level, :start_at, :end_at, :presence => true validate :event_takes_place_in_one_day, :event_is_not_in_past def event_takes_place_in_one_day self.start_at.day == self.end_at.day end def event_is_not_in_past admissible_range = DateTime.now.beginning_of_day..DateTime.now.end_of_month admissible_range.cover?(self.start_at) && admissible_range.cover?(self.end_at) end I need to validate presence of start_at and end_at before my custom validations, but this do not happen, here is the errors that I got undefined method `to_datetime'' for nil:NilClass app/models/meeting.rb:22:in `cover?'' app/models/meeting.rb:22:in `event_is_not_in_past'' app/controllers/meetings_controller.rb:18:in `create'' -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org To view this discussion on the web visit https://groups.google.com/d/msg/rubyonrails-talk/-/dqXDEVOsjZcJ. For more options, visit https://groups.google.com/groups/opt_out.