Being able to overlook the 'obstacle to peace' that other people put in place is a tuff one. But it also means I have to be able to not have obstacles to peace in myself, and that I need to take any kind of 'veil' or 'persona' off of my own mind so that I can see past the personas of other people.
Being able to overlook appearances is forgiveness. When your awareness fixates on looking AT an appearance, AT a body, AT a person's form, this is blinding. "Nothing so blinding as sight of form" - ACIM. This is what happens when the Holy Spirit in you is not allowed to fully extend outward, instead being stopped by the form of another person. But it's not their form that stops your 'vision', it's your belief that it's real - your buying into the illusion of it.
There's sections in the Course that I read not long ago about how the Holy Spirit projects/extends outward PAST your own body and PAST the bodies of other people, to recognize Himself WITHIN the mind of the other person. When your mind is looking past these forms in this way, there is no sickness because the mind isn't getting 'stuck' on form. Fully extending THROUGH and PAST the body is COMMUNICATION, which the Holy Spirit wants to use it for - to join with others beyond their bodies. But if we're fixating on the content of form such as guilt, fear, sin, death, bodies, appearances, etc then this puts a road-block in the way of extension, creating sickness and death. The body then becomes an 'obstacle to peace' - it's in the way we're looking at or past things.
The truth is that the body is never in the way of a truly forgiving mind. The body is not powerful and does not have the ability to prevent the extension of love. The body (mine, or someone else's) also has no ability to snag my mind or get me to pay attention to it. Instead, if my mind is truly forgiving, it will simply see THROUGH and PAST the obstacle recognizing that it is not real and has no ability to prevent extension. Then there will be a recognition of Oneness with your brother.
The issue is that when the mind itself has blocks to awareness, these blocks prevent full extension of Spirit. And that means there's some kind of belief in or attachment to guilt/sin/fear/death/spacetime/bodies etc within the mind. That means, instead of the mind just moving past and extending past everything in form, it instead 'stops' at or becomes fixated on form as though it has some power to block your awareness/sight/vision. You focus on something which is NOT THERE, and you think it is real, and this blocks your awareness. Blocks to awareness manifest as blocks to energy flow and vitality, where ultimately a 'big block' brings about "death".
It's an ongoing challenge to learn not to fixate on form or appearance, especially when you are used to seeing other people as though they ARE the way they appear. So if someone comes along with a sickness or a story about themselves or a really attention-grabbing attitude etc, if I am tempted by that and look AT it and MAKE IT REAL then my mind has become snagged by it, attached to it, and resistant of it, and that will have an affect on my own wellbeing. It will make me sick because I am seeing my brother as sick by failing to overlook sickness. We need to literally see the Christ in ourselves and others in order for our mind to fully extend and to be unhindered and unrestrained. I think in the Course Jesus used a word like "arrested". When the mind is arrested by sight of form we become sick. When the mind is freed from arrest, sickness is loosened up and flow is restored and there is no more death.
It's difficult but I have to learn to look past the ILLUSION that people have something wrong with them, the illusion that people are really sick, the illusion that people are actually able to suffer, the illusion that people really have something to be afraid of etc. And this goes back to the first point.... .underneath all of our shit there is an immortal being that is absolutely unaffected by any illusion and has no faults and is perfectly innocent, invulnerable, powerful and free. If I believe that and know that and experience that and look TO that, then I will overlook all the other illusory bullshit. But if I forget that, or lose sight of that, or fixate on any other DEMONSTRATION as though it is the truth about me or another person, then now I'm into la-la land, hallucinating, suffering, caught up in stories, reacting to appearances and struggling with my own self.
I'm looking forward to absolute certainty. Someday it will appear within and without simultaneously. We are all really free, we just don't recognize it.
(anecdotal. .... People looking down at their iPhones fixated on form, hmm... A great way to make illusions real and to shut out everything else, and they call this a 'communication' device lol it's really an isolation device :-)..depending who you're dialling with ;-)