tefilla - Why do we pray?

Say you have a very good king--he is very nice to his servants and makes the country prosperous and peaceful for everyone. Wouldn't he find it annoying if one of his servants praised him daily, three times a day: for one hour in the morning, 30 minutes in the afternoon and another 30 minutes in the evening. Wouldn't the king prefer for his servants to continue carrying out his commandments to continue the success of the country?

We do exactly that: Shacharit, Minhah and Arvit. Also halalchically speaking--aside from reading the Shema twice a day--is it a commandment derabanim to pray shemonah esray and the rest? A source would be appreciated.

Answer

"Moreover, as for me, far be it from me that I should sin against the LORD in ceasing to pray for you; but I will teach you the good and the right way." 1 Sam 12:23

As Samuel considered it a sin to cease praying for the Children of Israel, should we likewise consider it a privilege to pray to G-d for each other? We should not cease to pray. Prayer should not be only 3 times a day, but instead a lifestyle where we constantly talk to Abba. When my daughter was 3 she talked constantly and it was both fun and annoying to listen to her. I don't think Abba is ever annoyed with us... maybe amused but not annoyed. He wants to hear from us. Prayer is a conversation... talking is great, but to have a relationship requires us to be quiet sometimes and wait for Him to speak. Without quiet time there is no prayer... just a bunch of one way talking. Prayer shows we NEED Him in our lives and that we believe in Him. And by listening (and obeying) we show Him our respect. If you are merely reciting a bunch of canned speeches... it's not prayer, it's tradition. Tradition has its place to maintain the continuity of the faith to provide a benchmark and an example for others to follow. It's like feeding Vegimite to your children. It's good for them, but when they are older they need steak. We continue what tradition calls prayer for the sake of the community and for others to learn from and follow (because if you truly listen to those canned speeches there's a lot of heart in them), but true prayer is continually talking to G-d and taking those quiet times to hear from Him.