Lambert edged out West Ham striker Andy Carroll for a spot in England's 23-man squad after netting 13 Premier League goals for Southampton this season.
The 32-year-old's selection caps a remarkable rise as, this time four years ago, just prior to the 2010 World Cup, Lambert had just completed his first season with the Southampton, who were still playing in the third tier of English football.
Lambert is now set to compete at his first World Cup, where England will face Italy, Uruguay and Costa Rica, and he lauded the impact of the man that introduced him to international football against Scotland last year.
"He has been brilliant for me since the very first moment I got a chance," said Lambert, who has scored two goals in four appearances for England thus far.
"The little conversations we have here on the training pitch, he emphasises that I am a good player, he understands the career I have and he appreciates it, because he knows how much it means to me.
"He constantly gives me the confidence that he believes in me, and that's what I need as a player, that's what every player needs. So he's top drawer."
Lambert is not the only Southampton representative in the team, with skipper Adam Lallana and Luke Shaw also in the squad.
England open their World Cup campaign against Italy in Manaus on June 14.
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