Should I confront him or keep quiet.  

Good day house, please I need your advice on how to go about this. I've been with my husband for 9 years, married for 4. I've never ever doubted his fidelity. He's God fearing, a church worker, prayer warrior, speaks in tongues. In fact he's perfect.  He's never given me reason to doubt him or be suspicious. I thought it was kind of strange when he downloaded Facebook; he doesn't do social media. I have Facebook, Twitter and Instagram accounts, but I'm not very active. He said his friends have been begging him to join Facebook so as I said, I've never had any reason not to trust him. So I thought nothing of it. This morning, my husband was in the shower and left his phone on the bed. I was half-asleep when his phone started getting messages and woke me up. I thought it was my phone as I was half awake. He does not password his phone. I didn't even notice and I looked at notification from Facebook. It said message from "Aunty K**e". I was curious so I open the message, this 'Aunty K**e' had sent him a picture of her private part. The message said "I want your tongue inside me again". Now. I immediately thought it was a mistake. But I was alert now after being awoken by this image. I looked at his previous messages with her and saw that they had met on Friday night. We went to church today like normal and I just couldn't imagine how he can do this to me. We're happy. I thought we were happy. We have s.x at least 6 times a week. I just don't understand how he could do this. We have 2 children together. Should I confront him or keep quiet.