An encourager comes alongside someone to give courage and hope.  Many of the verses in the KJV use the word "Comforter" but in the Greek it can also be translated "encourage, encourager".  It is the Greek word parakaleo with the basic meaning "to call or summon to one's side".

II Corinthians 1:3-5 in the Working Translation by Rev. Walter Cummins:

"Blessed is the God and Father of our Lord Jesus Christ, the Father of compassion and the God of all encouragement, Who encourages us in all our affliction so that we may be able to encourage those who are in any affliction by means of the encouragement with which we ourselves are encouraged by God. Even as the sufferings for Christ abound in us, so our encouragement also abounds by Christ." 

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