As a witness for Peace, our role was to witness in two senses of the word: we SAW, and by our presence we offered affirmation by word or example of a solidarity based on love and faith and the Good News. The word that is much used is "accompaniment." Our contribution was less in our doing than our being-with.
Silence admits of many degrees ... but the greatest silence is that of our spirit with God's Spirit: Heart speaks to heart in silence, the language of self-surrendering love.