People often forgive others externally (thru gestures, words, actions etc), but I feel that the true forgiveness is about gracefully letting go of the pain or hurt that we experience within (this pain or hurt we believed was caused by an external event or a person). This "letting go" is more of an internal shift than anything external. I feel that this internal shift within the person forgiving manifests in the form of compassion towards others.
A Monk in his travels once found a precious stone and kept it.One day he met a traveler and when he opened his bag to share his provisions with him,the traveller saw the jewel and asked the monk to give it to him.The monk did so readily.The traveler departed overjoyed with the unexpected gift of the precious stone that was enough to give him wealth and security for the rest of his life.However ,a few days later he came back in search of the monk,found him ,gave him back the stone and entreated him,"Now give me something much more precious than this stone.Valuable as it is .Give me that which enabled you to give it to me."
This traveler knew for certain that the monk possessed something much more precious than this jewel.That is why he came back looking for the monk.It was the spirituality of the monk the traveler was asking for.