Humbly receive something and you'll be humbly receiving it. Or humbly eating it if they gave you food and not a puppy or something inedible. It can also mean humbly having. The theme here is humility!

This is usually formal when written in kanji and used together with a verb like する. It can also be used alone to make very casual requests. In casual requests, it's still written in kanji in novels and other creative writing, but is generally written in hiragana anywhere else.