But the people took some of the spoil, sheep and oxen, the choicest of the things devoted to destruction, to sacrifice to the Lord your God at Gilgal."Two things that are interesting in Saul's statement here. First, he blames the people for keeping spoil, as if he were powerless to stop them. He's the king, and he was to have issued a command. In an entire army, it shouldn't be that difficult to notice a big herd of livestock. If he had wanted to follow God's command, he should have been able to easily, without some excuse.
The second thing that hit me was that he doesn't talk about "the Lord our God," or even "the Lord their God," he says "the Lord your God." In other words, assuming this is translated accurately, he doesn't really believe all this claptrap about God's power or the need to follow His commands, and he doesn't think the people really do, either. He only thinks Samuel believes it, and that the people are just kinda following along to humor him, or at least have divided loyalties. If it ever came down to it, Saul certainly doesn't believe that God is supreme, he just puts on the airs.