The principle that all Commandments are weighted equally has, as do many core religious principles, a light and dark side.On the one hand, it (theoretically) prevents someone from ignoring one of the important commandments just because they personally disagree with it or find it trivial ("Thou shalt not kill? Clearly that's more of a guideline than an actual rule!"). On the other, it leads to a certain degree of insanity, when "Put fringes on the corners of your garments" carries equal weight as "Do not rape". Imagine how ludicrous it would be if comparing the record of two people: "Well, the guy on the right is a murderer, but the guy on the left has unfringed garments and left the table without saying the proper blessing! No question which one we want as our Sunday School teacher!"
In practice, all Commandments are not weighed equally. We know this because the punishments do not all match. The punishment for masturbation is, essentially, having to take a shower. Killing someone's ox requires you to pay its full value. Practicing witchcraft gets you put to death. These all may be equal in terms of which ones we have to take seriously, but economic theory alone would quickly develop some rankings. I definitely won't practice witchcraft, and I can't afford to kill my neighbor's ox until after payday, but I was planning to take a shower tonight anyway, so...
And this is a good thing, because most of us walk around every day carrying at least some load of minor sins on our backs. In fact, there's a rather popular story featuring Jesus on this particular theme. Religion sets a basically inhuman, unachievable level as the ideal, which is ok because it's a goal to aspire to, not an achievement to be reached.
But if religion knows that we can't be perfect, and that we will, most of us, commit at least a few small sins per day (and if you think you're better than that, you just committed the sin of Pride; so there!), then maybe the goal of religion is not, in fact, for us to avoid all sin but rather to show us ways to reduce our wicked ways, and make amends when we do stray. In fact, at least three of the major Judeo-Christian religions have this worked into the core of their fabric, and offer fairly regular opportunities for repentance and forgiveness.
It occurred to me today while I was reading a post about religious tolerance for homosexuality (gasp!) that most people assume religion has this all-or-nothing approach to sin. Why else would people get so worried for their gay friends? Are we assuming that if the gayness did go away they would suddenly be free of all other vices as well? Or that homosexuality is the only thing they're doing that God would disapprove of?
Of course not; both those ideas are ridiculous. But this idea still persists that religion exists in some Judge Dredd-style universe, where littering, jaywalking, playing music too loudly, and speeding all carry the same potentially lethal punishment.
(This also reminds me of Father Guido Sarducci's bit "Life is a job". According to him, after death you get paid your wages based on how long you live; after that you have to pay God back for your sins. Murder, he figures, is a major crime worth at least $1,000; masturbation is only a quarter since it's a cheep thrill. Still, he keeps having dreams where he's a recently-deceased old man trying to get into heaven, and is just 25 cents short. As if a loving God would deny someone paradise for such a trivial reason.)
We are sinners all. We are meant to sin, to fail, and to be forgiven, purified, and renewed. It's built into the system, probably into our very DNA. You wouldn't have to tell people not to do these things if there wasn't some naturally occurring urge to do them.
So let people sin. Tell your friends you're concerned for them if you think they go too far, and remember that, as with any freedom, your right to sin ends at the beginning of my personal space.
Does that make it right? No. But it puts our focus where it needs to be; not on avoiding all sin to remain innocent and pure, but to learn, to understand, why these acts are considered sins. To internalize that message so that, gradually, we want to and are able to live a better life. And to recognize when we have done wrong and make amends.