His Purpose connects to the why question: why did God create everything that He did? 

He created things so they would magnify Himself.  He created things for His own pleasure, for His satisfaction and enjoyment.  He created things for his own Glory, so that the things that He created could see and experience the weight of His own character.

God created everything to Magnify Himself.

Psa. 19:1-14

[1] The heavens declare the glory of God; and the firmament sheweth his handywork.
[2] Day unto day uttereth speech, and night unto night sheweth knowledge.
[3] There is no speech nor language, where their voice is not heard.
[4] Their line is gone out through all the earth, and their words to the end of the world. In them hath he set a tabernacle for the sun,
[5] Which is as a bridegroom coming out of his chamber, and rejoiceth as a strong man to run a race.
[6] His going forth is from the end of the heaven, and his circuit unto the ends of it: and there is nothing hid from the heat thereof.
[7] The law of the LORD is perfect, converting the soul: the testimony of the LORD is sure, making wise the simple.
[8] The statutes of the LORD are right, rejoicing the heart: the commandment of the LORD is pure, enlightening the eyes.
[9] The fear of the LORD is clean, enduring for ever: the judgments of the LORD are true and righteous altogether.
[10] More to be desired are they than gold, yea, than much fine gold: sweeter also than honey and the honeycomb.
[11] Moreover by them is thy servant warned: and in keeping of them there is great reward.
[12] Who can understand his errors? cleanse thou me from secret faults.
[13] Keep back thy servant also from presumptuous sins; let them not have dominion over me: then shall I be upright, and I shall be innocent from the great transgression.
[14] Let the words of my mouth, and the meditation of my heart, be acceptable in thy sight, O LORD, my strength, and my redeemer.

God created everything for His pleasure.

Rev. 4:11

[11] Thou art worthy, O Lord, to receive glory and honour and power: for thou hast created all things, and for thy pleasure they are and were created.

God created everything for His Own Glory.

Isa. 43:1-7

[1] But now thus saith the LORD that created thee, O Jacob, and he that formed thee, O Israel, Fear not: for I have redeemed thee, I have called thee by thy name; thou art mine.
[2] When thou passest through the waters, I will be with thee; and through the rivers, they shall not overflow thee: when thou walkest through the fire, thou shalt not be burned; neither shall the flame kindle upon thee.
[3] For I am the LORD thy God, the Holy One of Israel, thy Saviour: I gave Egypt for thy ransom, Ethiopia and Seba for thee.
[4] Since thou wast precious in my sight, thou hast been honourable, and I have loved thee: therefore will I give men for thee, and people for thy life.
[5] Fear not: for I am with thee: I will bring thy seed from the east, and gather thee from the west;
[6] I will say to the north, Give up; and to the south, Keep not back: bring my sons from far, and my daughters from the ends of the earth;
[7] Even every one that is called by my name: for I have created him for my glory, I have formed him; yea, I have made him.