17 And to Adam he said,
“Because you have listened to the voice of your wife
and have eaten of the tree
of which I commanded you,
‘You shall not eat of it,’
cursed is the ground because of you;
The Holy Bible: English Standard Version. (2001). (Ge 3:17). Wheaton: Standard Bible Society.
Through the forbidden fruit, our relationship with each other is cursed. Note, yesterday, the personal effects of sin. But here the man is not cursed directly. Instead, the very ground is cursed. His labor will be increased and at death his body will return to the ground.
When we do things in private or we do things we think only affect us, think again. Our sins, even the things we do only to ourselves in the private of our home or the privacy of our mind can and do affect others. Adam did not answer Satan. But he ate of the fruit and the ground itself is cursed.
Sin affects the planet and the universe itself, not just people.