Halakhah su Isaia 64:10

2. One who sees Jerusalem in her destruction, says "Tzion is a desert, a desolation" (Isaiah 64:9) and rends (one's garments). And when one see the Bais HaMikdash says "Our holy Temple, our pride, Where our fathers praised You, Has been consumed by fire: And all that was dear to us is ruined." (Isaiah 64:10). And from where is one obligated to rend - from HaTzofim. And afterwards when he sees the the Mikdash, he rends another tearing. And all rendings are a tefach (handbreath). If one comes from the way of the desert that then he sees the Mikdash first. He rends on the Mikdash a tefach, and afterwards when he sees Jerusalem, he adds to the first rending a little bit.