Why You Should Never Touch the Hors d'oeuvres at a Canaanite Garden Party

They that sanctify themselves, and purify themselves in the gardens behind one tree in the midst, eating swine's flesh, and the abomination, and the mouse, shall be consumed together, saith the LORD. Isaiah 66:17


I think an additional translation of this verse is helpful:

"Those who 'consecrate' and 'purify' themselves in a *sacred garden with its idol in the center—feasting on pork and rats and other detestable meats—will come to a terrible end," says the LORD. NLT

* Or gardens behind one of your temples

In describing heathen rituals, Isaiah says it was customary to assemble in gardens to perform rites. There the heathen (and the Israelites who participated in heathen rituals) would gather "behind one tree"--possibly a pole dedicated to a goddess-to eat things forbidden to the Hebrews, such as swine's flesh, rodents, and other abominable things.