For all have sinned, and come short of the glory of God.
Romans 3, 23

Therefore, just as one man’s trespass led to condemnation for all,
so one man’s act of righteousness leads to justification and life for all.
For just as by the one man’s disobedience the many were made sinners,
so by the one man’s obedience the many will be made righteous.
Romans 5, 18-19

"In Adam all die, and thus the world prostrate and requires to be set up again, so that in Christ all may be made to live.” - Origen

“Through him our forefather Adam was cast out for disobedience, and exchanged a Paradise bringing forth wondrous fruits of its own accord for the ground which bringeth forth thorns." - St. Cyril of Jerusalem

“Adam sinned and earned all sorrows; likewise the world after His example, all guilt." - St. Ephraem

“How then did death come in and prevail? 'Through the sin of one.'” - St. John Chrysostom

“Evil was mixed with our nature from the beginning…through those who by their disobedience introduced the disease." - St. Gregory of Nyssa

“But the things that come out of a person's mouth come from the heart,
and these defile them. For out of the heart come evil thoughts-murder, adultery,
sexual immorality, theft, false testimony, slander.”
Matthew 15, 18-20