What does this quote illustrate? "These violent delights have violent ends / And in their triumph die, like fire and powder / Which as they kiss...

These words are uttered by Friar Lawrence just before he performs Romeo and Juliet's marriage ceremony.  References to honey and gunpowder may seem strange for a pre-wedding speech, but the crux of what Friar Lawrence is saying is that Romeo and Juliet need to slow things down a bit.  Like gunpowder and a spark coming together, things that are brought hastily together can sometimes explode.  Friar Lawrence also delivers these lines to help Romeo and...

These words are uttered by Friar Lawrence just before he performs Romeo and Juliet's marriage ceremony.  References to honey and gunpowder may seem strange for a pre-wedding speech, but the crux of what Friar Lawrence is saying is that Romeo and Juliet need to slow things down a bit.  Like gunpowder and a spark coming together, things that are brought hastily together can sometimes explode.  Friar Lawrence also delivers these lines to help Romeo and Juliet to understand that, in truth, what they are feeling at this point is more lust than love.  If they are to build a long-lasting marriage, they will need to love more "moderately" and pace themselves.  As he says, "Long love doth so."

What this illustrates is that, while the friar has consented to marry the two, he feels the need to warn them that their passion will dissipate as the marriage progresses and that they will need to build their marriage's foundation on more stable footing.  That is the key to a lasting marriage.  Sadly for Romeo and Juliet, they will never have a chance to put Friar Lawrence's advice into action.