Yesterday was, of course, Palm Sunday (aka Passion Suday). For those who don't know, in the Catholic Church the congregation participates in the proclamation of the Gospel. (To the best of my knowledge, it's the only time of the year that is allowed.) As a kid, I always felt uncomfortable when it came time for us to say "Crucify him!" because who wants to crucify Jesus?
It occurs to me the Church has us do that to remind us that when we sin, we are crucifying and rejecting Jesus just as those who shouted it originally did. It's our sins that put Him on the cross, and when we sin again we put him back there by choosing sin over Him, just as the people then chose Barabbas over Jesus.
We need to remember that when we are presented with temptation, or virtually any choice, there is the choice between what God wants us to do and and what God doesn't want us to. (Obviously, not every choice involves a potential for sin. The choice between pasta and seafood for dinner is unlikely to involve sin unless you took a vow to God to avoid one fo the other.) But we need to be careful when making choices that could lead to sin; we need to make sure that what we are doing is is accord with God's will so we don't put his Son right back on that Cross.
UPDATE: I forgot yesterday that the congregation also participates during the Gospel on good Friday. It's also the account of the Passion, but from John's Gospel.