Blessed be the God and Father of our Lord Jesus Christ, the Father of sympathy (pity and mercy) and the God [Who is the Source] of every comfort (consolation and encouragement), Who comforts (...) us in every trouble (calamity and affliction), so that we may also be able to comfort (...) those who are in any kind of trouble or distress, with the comfort (...) with which we ourselves are comforted (...) by God. (2 Corinthians 1:3, 4 AMP) For just as Christ's [own] sufferings fall to our lot [as they overflow upon His disciples, and we share and experience them] abundantly, so through Christ comfort (consolation and encouragement) is also [shared and experienced] abundantly by us. (2 Corinthians 1:5 AMP)f
God looks down from His throne and sees His child with a broken heart, or maybe he's weeping for sorrow for his sin, or she could be grieving. His heart goes out to them in mercy. When a person needs comfort the River flows from God alone. He comforts with a purpose in mind. That is to teach His child to comfort others the way He had comforted them and allow the River to flow through them.
Jesus suffered horribly on the cross and we have a part to play in His suffering. While we are on earth trouble will come to us, a bit of suffering. The reason is to identify with our Savior, feel what He felt, love in spite of ourselves, and forgive even amidst the pain. But if we suffer with Him there is an abundance of comfort that comes straight from our Savior. He's been there in His heart as well as physically and He went through it loving the people who caused His suffering, yes, asking "Why?," and giving Himself to His Heavenly Father. He's got a heart overflowing with comfort for us.