The Spaniard - who called the game "probably the most important" of the season as the club bids to regain ground on fourth place - paid credit to his predecessor for the work he did at the club.
"We all know how important the game is and how vital the three points are," Martinez told reporters. "All the nice welcoming is going to be after the final whistle. We have got a great understanding of who is coming back but we have to understand they represent the opposition.
"We will show the respect to David Moyes. His work has been terrific. As a former Everton manager, every Evertonian has got great memories of the job he did with the football club. [But] we need to make it as hostile as we can for the opposition."
Victory would give Everton its first league double over United in 44 years, but Martinez says another triumph against Moyes will not be easy.
"Facing the champions is always a reason to be excited," he added. "The opportunity to do the double on United is something that is not easy to achieve. In football it doesn't get any bigger than achieving something that takes so many years [to do].
"You need to remember, this team won the championship last season. You don't become a bad team overnight. There is always a bit of a transitional period as you get a new management team in place. They are really strong and we expect a very tough game on Sunday.
"We know that we are going to face a very strong team, it is more about how good we can be. And that is where the focus is."