Cause and effect is at work in the physical world according to the laws of physical matter. It is different in the internal worlds. What happens internally — psychologically, spiritually — is more powerful.
The internal worlds are those aspects of nature that we cannot perceive with our physical senses. In other words, we are multidimensional, not just physical.
As Tsong Khapa pointed out, actions produced psychologically (internally) have much greater effects than those produced physically (externally). This is partly because the physical realm is quite low on the scale of matter and energy. Moving up the scale, actions have greater consequences, because they “trickle down” to the lower levels.
Excerpts from Karma is Negotiable, Nikias Annas