Found this nice commentary on a website:
Finally, it must be considered that Jesus did, in fact, speak against homosexuality. On numerous occasions, Jesus condemned the sins of adultery (Matthew 19:18), sexual immorality (Matthew 19:9) and fornication (Matthew 15:19). These terms describe any type of sexual intercourse that is not within the confines of a marriage ordained by God. Jesus then proceeded to define exactly what God views as a morally permissible marriage. He stated:
Have you not read that He who made them at the beginning made them male and female, and said, “For this reason a man shall leave his father and mother and be joined to his wife, and the two shall become one flesh”? So then, they are no longer two but one flesh. Therefore what God has joined together, let not man separate (Matthew 19:4-6).
By defining marriage as between one male and one female, Jesus effectively condemned all other arrangements, including but not limited to one man and two women, one woman and two men, three men and one woman, three men and three women, one man and one man, one woman and one animal, etc. You can see the overwhelming logic of such. For Jesus to have to explicitly condemn every assortment of genders and numbers would be absurd. When He defined marriage between one man and one woman, He clearly showed that such an arrangement is the only one authorized by God.
Several years ago a man named Cory Moore “legally married his 2004 Cherry ES-335” Gibson guitar (“Man Marries Guitar,” 2007). He said: “The day I got her, I just knew she was the one…. I know it seems weird, but I really love her—like, really love her, with all my heart. I just wanted to make it official” (2007). Are we to conclude that because Jesus never specifically condemned a man marrying his guitar then the Son of God approved of such? To ask is to answer. In 2006, 41-year-old Sharon Tendler married a dolphin (“Woman Marries Dolphin,” 2006). Jesus never said one word explicitly about refraining from marrying a dolphin. Does that mean His “silence” should be viewed as approval? Not in any way.
Homosexuality is a sin. It always has been, and it always will be.