The "Comforter" is one of the characteristics of God, the manifestation of His Will toward man. 
"The "Comforter" is God, Who, guarding man by His covenants, His gracious Commandments, so creates for him all the necessary conditions for a life of righteousness, so "comforts" him, encourages him, protects him, protects him, "raises him up" by His reviving Laws to His spiritual "Image" and "Likeness".
"Comforter" is the Spirit of God's Word, the meaning, the essence of which "quenches" the sinful passions, the motives of man's flesh, pacifies his prideful temper, gives comfort to man's spirit, soul and body. 
"Comforter" is the Will of God, His Laws, Commandments, which, if executed by man, are his "consolation", i.e. serve him as a protection from the consequences of their violation, help in resolving the spiritual goals set by man and a support, a guide in his practical and spiritual life.