I had to put him down.

We're on our own.

The only reason you're still breathing is because one of us is still human.

Glad to see you picking up your psycho boss' old habits.

Diggle: Damien Darhk is no one's savior. He's a liar and a monster.
Andy: The Romans said the same thing about Jesus.

Oliver is leaving tonight for a magical mystery tour and wants me to stay put.

I'm so angry, I can hardly breathe.

Diggle: We need to go.
Oliver: Where?
Diggle: Somehwhere where I'm going to try to trust you again.

Diggle: I would think you. of all people, would understand keeping secrets when it comes to the death of a sibling.
Laurel: I do. And because I do, I can tell you carrying a burden like that never ends in any way but bad.

Oliver: He left behind evidence.
Diggle: Fingerprints.
Laurel: How'd you get the owner to part with his windshield?
Oliver: I bought his truck. It's one of the benefits of your girlfriend inheriting a multi-billion dollar conglomerate. We have money now.

Oliver: I'm looking for a way in.
Diggle: I was furious to think that you trusted Malcolm Merlyn more than you trusted me, but then I realized that I'm not angry with you, I'm angry at myself for thinking you're someone that you clearly aren't.
Oliver: I don't know what that means.
Diggle: Oliver, after everything we've been through, man, I couldn't fathom why you didn't trust me. Then I realized you couldn't. It's not who you are. You don't trust. You don't love. You were able to fool Ra's and join the League because inside you are every bit as dark as they are.

Felicity: I can't believe he's gonna marry her.
Malcolm: You should worry more about getting out of here alive.
Ray: Is that even a remote possibility?
Laurel: Oliver would never let that happen.
Diggle: He let this happen.

Arrow Quotes

Do you know why I always blame myself in situations like this? Because at least it's an answer. Sometimes we just need a reason when a situation is completely unreasonable.

Oliver

Laurel: Helena, you don't have to do this.
Helena: Yes, I do. Because once you let the darkness inside, it never comes out.