On the premiere episode of I Am Cait, we saw Caitlyn Jenner introduce her true self to her mother, Esther Jenner. It was emotional watching Esther struggle to understand and accept Caitlyn. Though I will say this for Esther: She was actively interested in understanding everything, and she made it very clear that she will always love Caitlyn, no matter what. But on I Am Cait , Esther did bring up a seemingly anti-transgender Bible passage that says a "man" can't wear "a woman's cloak" and asked Susan P. Landon from the LA Gender Center if she has "any interpretation of that?" Landon responded, "Caitlyn is a woman, and really always has been." The implication seems to be that this passage does not apply to Caitlyn.
I don't think Esther's intent was negative; it seemed she was just genuinely curious about everything and was seeking a way to understand Caitlyn's transition through something presumably familiar to her, like religion.
The passage in question comes from Deuteronomy 22:5, and reads as follows according to the official King James Bible:
A woman shall not wear a man's garment, nor shall a man put on a woman's cloak, for whoever does these things is an abomination to the Lord your God.
This verse uses different language across multiple versions of the Bible. Below are some of the iterations:
A woman must not wear men’s clothing, nor a man wear women’s clothing, for the Lord your God detests anyone who does this.
A woman shall not wear a man’s garment, nor shall a man put on a woman’s cloak, for whoever does these things is an abomination to the Lord your God.
A woman must never wear anything men would wear, and a man must never wear women's clothes. Whoever does this is disgusting to the Lord your God.
Many have criticized the Deuteronomy section of the Bible for being inherently sexist and overly judgmental. But the Deuteronomy is a part of the Old Testament, which many practicing Christians no longer adhere to, because per some interpretations, the New Testament came along and made the old rules irrelevant.
At first sight, this may seem like the Bible is making an argument against transgender people, if you believe the Bible is the be all end all when it comes to evidence for arguments. (I don't, for the record.) However, if you follow this passage to the letter, that argument doesn't really work. As Landon said during I Am Cait — and this is the most important part — Caitlyn and other transgender women are women, so this "rule" has nothing to do with them.