be as good as (one's) word

To be reliable and truthful. Said of one who typically follows through on one's promises. Tom is as good as his word—if he promised to help you move, then he'll be here. Why are you surprised to see me? I said I'd work on your campaign with you, and I'm as good as my word. I'll be there tonight, don't worry. I'm always as good as my word.

be as good as your word

do what you have promised to do.

be as ˌgood as your ˈword

do what you have promised to do: You’ll find that she’s as good as her word — she always comes if she says she will.