Sure! Be a fan! Give him the plate, but ask LOTS of questions. You can make GM moves right from the get go. 'Tell him the consequences and ask', remember?
Where did you get your armour?
Which armourer made it?
What does it mean to you?
What would you do if it was damaged or stolen?
Tie in bonds. Do you have a thief? Ask provocative questions. 'Hey thief? Did you steal the Paladin's armour once? Why?'
Then open the game with action, remember? Have the armourless paladin confront the witch who purloined his armour (instant stake question - why did she do that?!), with the townsfolk selling her out to safe their own necks, (given the paladin's history). Except that the witch is the wizard's mentor, or the fighter's mum, or the armourer's wife or something tied in to the player's playbooks. Front load the situation with tension and conflict and make the paladin's armour the big deal the player wants it to be :)