What is reap?

“The daughter of debate, that eke discord doth sow,
Shall reap no gain where former rule hath taught still peace to
grow.
No foreign banished wight shall anchor in this port;
Our realm it brooks no stranger’s force, let them elsewhere resort.”
—Elizabeth I (1533–1603)

“Like a tale of little meaning though the words are strong;
Chanted from an ill-used race of men that cleave the soil,
Sow the seed, and reap the harvest with enduring toil,
Storing yearly little dues of wheat, and wine and oil;
Till they perish and they suffer—some, ‘tis
whispered—down in hell”
—Alfred Tennyson (1809–1892)

“Do good, reap good; do evil, reap evil.”
—Chinese proverb.