diff --git a/hook.c b/hook.c
index bc1c45b16d..b8ed4d79e2 100644
--- a/hook.c
+++ b/hook.c
@@ -408,7 +408,11 @@ static int pick_next_hook(struct child_process *cp,
 	} else if (h->kind == HOOK_CONFIGURED) {
 		/* to enable oneliners, let config-specified hooks run in shell. */
 		cp->use_shell = true;
+		if (!h->u.configured.command)
+			BUG("non-disabled HOOK_CONFIGURED hook has no command");
 		strvec_push(&cp->args, h->u.configured.command);
+	} else {
+		BUG("unknown hook kind");
 	}
 
 	if (!cp->args.nr)