'Enemy' in the Bible

Ye have heard that it has been said, Thou shalt love thy neighbour and hate thine enemy.

but while men slept, his enemy came and sowed darnel amongst the wheat, and went away.

And he said to them, A man that is an enemy has done this. And the bondmen said to him, Wilt thou then that we should go and gather it up?

and the enemy who has sowed it is the devil; and the harvest is the completion of the age, and the harvestmen are angels.

Behold, I give you the power of treading upon serpents and scorpions and over all the power of the enemy, and nothing shall in anywise injure you.

said, O full of all deceit and all craft: son of the devil, enemy of all righteousness; wilt thou not cease perverting the right paths of the Lord?

If therefore thine enemy should hunger, feed him; if he should thirst, give him drink; for, so doing, thou shalt heap coals of fire upon his head.

The last enemy that is annulled is death.

So I have become your enemy in speaking the truth to you?

and do not esteem him as an enemy, but admonish him as a brother.

Adulteresses, know ye not that friendship with the world is enmity with God? Whoever therefore is minded to be the friend of the world is constituted enemy of God.