I believe there is a God because it makes sense to me; the most sense of all the possibilities. I'm not trying to be antagonistic here but if that wouldn't satisfy your question, I wouldn't really care. By belief in God neither requires you to share that belief nor sanction it. I do expect, if you wish to be considered a rational part of society, that you tolerate my belief, which is to say don't persecute me for it, and don't deny me any generally accepted rights based upon it. It would also be nice if you didn't hector me to explain my belief to your satisfaction (which is not to say you engage in this behavior).
I've no problem with your being curious as to why someone might believe in any particular part of the Bible such as Jesus died for humanity's sins. It's perfectly reasonable to ask someone if they would share the reasons for their beliefs, but it is rude to do so if your only interest is to create an opportunity for mocking them for their belief, or if they decline and you persist.
Perhaps one day you will receive an answer you've never heard before and that will be interesting, and I suppose it's always possible that you might even receive an answer that convinces you of their belief. I very much doubt both the former or the latter, but there's no harm in asking in good faith.
If, on the other hand, one of these people engages in proselytizing, "answering" questions never asked, and attempts to convert you, then I don't think it's wrong to tell them you think they are talking nonsense and are not interested. If they persist, I think a certain amount of rudeness is justified too.
The statement with which Debra apparently has such a problem, cannot be considered proselytizing, but it's not exactly invited either (although I suppose one could argue that if you found it, you were essentially inviting it) and I see nothing wrong with expressing the opinion that it doesn't make sense to you. There's also nothing wrong with expressing the opinion that you find it offensive and contradictory since we do have free speech, but I for one would hold you in higher regard if the source of offense was obvious to the so-called "reasonable man," or you at least tried to explain it.
I can appreciate that people find religion to be superstitious nonsense and that its acceptance can in some way harm the individual or even society, but the degree to which such harm is inflicted or whether or not any harm is actually generated is obviously based what makes up a person's religion.
If someone believes that every first born son should be sacrificed to their God, the harm inflicted is quite obvious. If, instead, they believe that they should love their fellow humans and strive to do good needs, because their Gods wants them to, I don't see any harm at all; quite the contrary.
If you believe that the earth is 5,000 years old, that humanity co-existed with dinosaurs and/or that every person who has ever lived or will live is the direct descendant of a male and female homo-sapien; instantaneously brought into being as adults, then, in my opinion, you are ignorant and/or self-deluded, and if there is any harm inflicted by these beliefs, it is minimal and isolated to you. I am not going to seek opportunities to disabuse you of or mock you for these beliefs. I'm not going to ask you to explain how you these beliefs can be true, because they cannot be. However if you choose to get in my face with these beliefs I will tell you that you are ignorant, and if you try and force them on other people I will resist your efforts.
I still cannot see how the statement "I do not support homosexuality or homosexual marriage" can be considered offensive by the reasonable man
. If someone says they do not condemn homosexuals, can love and befriend homosexuals and will seek to protect them from persecution, my first thought isn't that they are crazy, liars, or hypocrites because they also say they are a Christian and believe in the Bible. It seems to me that the people for whom this is their first thought are guilty of rampant generalization or the very bigotry the ascribe to the people making the statement. As they feel the need to point out bigotry when they see it, so do I.
I particularly dislike when people distort the concept of tolerance to bolster what they personally believe. In our current society, for good or bad, "tolerance" has become an almost sacred value, and few people are comfortable being perceived, rightly or wrongly, as intolerant. This is a good thing in that the true concept of tolerance should be a fundamental value of our society, but it is a bad thing because intellectually dishonest bullies are very happy and all too quick to distort it for attacks against those who do not share their beliefs.