My 6 year old daughter and I were in the deep end of a wave pool at a water park, the waves were pretty big, and she was being bounced about. I was moving around, trying to keep close by her in case she needed help, when another adult inadvertently got between us. That aroused a burst of anger in me because I perceived that he hindered my ability to get to my daughter. He quickly moved past, and so did my anger, but the experience left an impression.
God likely feels something like that when things get between us and Him. He wants to be there for us, and must be similarly angered when people/relationships/other things interfere with His access to us. See e.g. Deuteronomy 6:10-19 and Exodus 34:12-16.