echthros (Greek #2190)
hateful (passively, odious, or actively, hostile); usually as a noun, an adversary (especially Satan)
KJV usage: enemy, foe.
Pronounce: ech-thros'
Origin: from a primary ἔχθω (to hate)
latreuo (Greek #3000)
to minister (to God), i.e. render religious homage
KJV usage: serve, do the service, worship(-per).
Pronounce: lat-ryoo'-o
Origin: from λάτρις (a hired menial)