“Jesus did explicitly define marriage as being between one man and one woman.”
At creation, God took the woman out of the man. In marriage, they are re-united. No room there for any other sort of “coupling”.
Perverted homosexuals think with a perverted mind. So yes, they will read something different.
The list of behaviors that Jesus did not specifically condemn would be very long. He failed to mention such offenses as,
Child abuse
Embezzlement
Blackmail
Rape
Kidnapping
Torture
Cruelty to animals.
Oh the list goes on and on. Does that mean if people start claiming that they were born with the desire to hurt baby bunnies we must affirm this behavior and call it good because Jesus did not say “hey put down that stick and leave the bunny alone!”? Didn’t think so.
The Scripture makes very clear there is only one form of sexual union sanctified by God and homosexual fornication ain’t it. Sodomy is one of the four sins that cry to heaven they are, willful murder, sodomy, oppression of the poor (especially the widow and the orphan) and defrauding a worker of his rightful wages.
All of this comes from admonishments in Scripture that such things are a great offense to God.