God decides one day that it's time for Adam and Eve to become intimate with one another, so he has Adam come to him in a clearing, while Eve waits for him in a forest.
"Adam, I want you to walk up to Eve and give her a kiss."
"Lord?" asks Adam. "What's a 'kiss'?"
God explains that it's what occurs when he and the woman would press their lips together. Adam goes into the forest, and returns with a smile on his face.
"She liked that!" Adam smiles.
"Very good, Adam. Next, I'd like you to caress her breasts."
"Lord?" asks Adam. "What are 'breasts'?"
God explains where they are on Eve's body and how to touch them. Adam goes back into the forest, and comes back a couple minutes later, a smile on his face.
"She liked that, too!" Adam grins.
"You're doing very well, my son. I believe you're both ready to consumate your relationship and have sexual intercourse."
"Lord?" asks Adam. "What's that?"
So God tells him exactly what to do. Adam re-enters the forest, but comes back a minute later, a look of confusion on his face.
"Adam, what happened?" asks God. "It should have taken longer than a minute."
So Adam replies, "Lord? What's a 'headache'?"