I’ll support unrestricted, taxpayer-funded abortions as soon as you convince me that the unborn aren’t human beings and I’ll support government recognition of “same-sex marriage” as soon as you prove that these couples can provide a mother and a father to a child.
In both cases it is biology, not bigotry, so don’t let people silence you on these crucial topics.
You don’t have to convert people to your point of view on marriage or abortion before sharing the Gospel or pointing them to the Bible. But for many people these are barriers to even considering Christianity. Just having a few replies — literally just a minute or so — is often all it takes. You can simply say, “Yes, the Bible does say it is a sin but even if it didn’t we are still separated from God by our many other sins . . .” and then point them to the cross and to God’s word (same thing for the abortion issue). Here’s a real-life example of how to do that.
If people are hostile to it, then hold your pearls. But don’t give up before you try.