In what way is homosexual expression/orientation harmful to either party (assuming both are consenting adults)? (To say, "Because the bible is against it" would represent circular logic). If you can name one valid way that homosexual orientation or expression is harmful to either party, I'll leave you alone. But it has to be valid.
As a note, anyone who quotes Leviticus on ones prohibition should to be complete including all the other things that are included in a very extensive list. Cherry picking through the list of 76:
3. Eating fat (3:17)
12. Letting your hair become unkempt (10:6)
15. Eating an animal which doesn’t both chew cud and has a divided hoof (cf: camel, rabbit, pig) (11:4-7)
23. Going to church within 33 days after giving birth to a boy (12:4)
24. Going to church within 66 days after giving birth to a girl (12:5)
39. Having sex with a man “as one does with a woman” (18:22)
42. Reaping to the very edges of a field (19:9)
43. Picking up grapes that have fallen in your vineyard (19:10)
48. Holding back the wages of an employee overnight (not well observed these days) (19:13)
54. Mixing fabrics in clothing (19:19) (KJV: linen and woolen)
55. Cross-breeding animals (19:19)
56. Planting different seeds in the same field (19:19)
60. Trimming your beard (19:27)
61. Cutting your hair at the sides (19:27)
62. Getting tattoos (19:28)
75. Selling land permanently (25:23)
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