Does it sound like he cheated?

My partner rarely stay out for the night, until this one night where he went out to drink w his coworkers. He left at 4pm, didnt come til the next morning, and didnt even let me know about it either til 1am, thats hes staying for the night.

So, today he was talking about trust. He said that there shouldnt be too much trust in a relationship, or else one of them is going to take advantage of it, and cheat. Knowing that their partner wouldnt have any suspicions of it cause they trust him/her too much. He said ppl needs to be smart and not trust too much, or they will get fucked over. He told me he wont accept me staying the night out, cause he knows i will get seduced, and cheat on him. If i want to go out, i need to take the kids, so i wont be abke to cheat on him.

He began talking about how this guy he knew, was doing sexual things w a woman he just met at a party, and he lied to his wife that hes drunk, and cant come home, but what hes really doing was having sex w that woman.

Now i just feel like he probably cheated that night, and i feel like he was actually talking about himself cheating on me. And he never wants to bring the kids w him, or wants me to go along w him.

Idk anymore, it bothers me a lot, i just know it that he cheated that night. He denied it though, but i have a feeling hes lying.