The question I asked was why does life need a purpose. Perhaps I asked an unanswerable question.
Possibly. If you think about it life doesn't need a purpose, but each and every person gives it purpose by creating and fulfilling goals. So from a fundamental sense each and every person creates their own purpose. But another question would be whether life has a purpose common to all outside personal goals. This is where proof is going to be lacking and religion steps in to give answers to questions which cannot be sufficently proven to date.
You gave a what the purpose is...that we were created to worship God. Like a fish I'm going to bite on this hook.
Why would God want or need us to worship Him? God is suppose to be perfect and complete. Is God lacking something that He needed to create us to worship Him? What does He get from our worship?
Though I'm very interested in hearing the Muslim veiw on this other theists can also share their views.
The best I can do to respond to your questions may not be satisfactory, but I'll attempt my best none-the-less.
First of all, yes God is supposed to be perfect/complete and doesn't need us as shown in the following verses:
051.057
YUSUFALI: No Sustenance do I require of them, nor do I require that they should feed Me.
PICKTHAL: I seek no livelihood from them, nor do I ask that they should feed Me.
SHAKIR: I do not desire from them any sustenance and I do not desire that they should feed Me.
"Them" is referring to Jinn and Humankind as noted in the verse before this one, which I already cited in an earlier post.
051.058
YUSUFALI: For Allah is He Who gives (all) Sustenance,- Lord of Power,- Steadfast (for ever).
PICKTHAL: Lo! Allah! He it is that giveth livelihood, the Lord of unbreakable might.
SHAKIR: Surely Allah is the Bestower of sustenance, the Lord of Power, the Strong.
002.255YUSUFALI: Allah! There is no god but He,-the Living, the Self-subsisting, Eternal. No slumber can seize Him nor sleep. His are all things in the heavens and on earth. Who is there can intercede in His presence except as He permitteth? He knoweth what (appeareth to His creatures as) before or after or behind them. Nor shall they compass aught of His knowledge except as He willeth. His Throne doth extend over the heavens and the earth, and He feeleth no fatigue in guarding and preserving them for He is the Most High, the Supreme (in glory).
Since this verse is somewhat larger than the others I'll just cite one translation. If you wish to view others here is a link to the verse in 3 translations:
http://www.usc.edu/dept/MSA/quran/002.qmt.html#002.255
One of your questions is:
Is God lacking something that He needed to create us to worship Him?
Well from an Islamic point of view, No. However if you don't hold the Islamic point of view to be true, then it is possible to come to the conclusion that God isn't perfect and is lacking in some sense.
Your other two questions are very similar so I'll respond to them together:
Why would God want or need us to worship Him? What does He get from our worship?
These two questions are somewhat hard to answer, since God didn't exactly spell out the answers. At least not directly. First of all, Islam holds that God doesn't NEED us, therefore God doesn't NEED worship from us. However, Islam also holds God WANTS us to worship him, that's the universal purpose of life as cited by the Qur'an. So it is natural to wonder why God would demand something God doesn't need. Well one natural response would be the following:
What if humans need worship? Is it not possible worship isn't for God, but for humans instead? Just a thought. Maybe worship is in some way healthy for our being or simply good for us. This response came to me because of the following verse (There are other similar verses):
003.108YUSUFALI: These are the Signs of Allah: We rehearse them to thee in Truth: And Allah means no injustice to any of His creatures.
PICKTHAL: These are revelations of Allah. We recite them unto thee in truth. Allah willeth no injustice to (His) creatures.
SHAKIR: These are the communications of Allah which We recite to you with truth, and Allah does not desire any injustice to the creatures.
God wants what is best for us, good for us.
Beyond that I can currently think of no other response that would allow me to conclude God is perfect/complete/self-sufficent and yet demanding of worship.
Obviously my response isn't meant to convience non-believers that it is the truth, but to only show a possible train-of-thought which would allow the belief that Islam holds to not be logically contradictory.
If you have any more questions I'd be glad to respond to them as best I can.
Thanks
Peace