God is omniscient; He has all Knowledge.  

God knows everything. There is not anything that can be known that God is not know. There is no limit to his absolute knowledge.

Since God knows everything, he knows what is best for you.

Rom. 11:33

[33] O the depth of the riches both of the wisdom and knowledge of God! how unsearchable are his judgments, and his ways past finding out!

 Isa. 55:8-9

[8] For my thoughts are not your thoughts, neither are your ways my ways, saith the LORD.
[9] For as the heavens are higher than the earth, so are my ways higher than your ways, and my thoughts than your thoughts.

Matt. 10:29-30

[29] Are not two sparrows sold for a farthing? and one of them shall not fall on the ground without your Father.
[30] But the very hairs of your head are all numbered.

Psa. 56:8

[8] Thou tellest my wanderings: put thou my tears into thy bottle: are they not in thy book?

Ex. 3:7

[7] And the LORD said, I have surely seen the affliction of my people which are in Egypt, and have heard their cry by reason of their taskmasters; for I know their sorrows;

Psa. 34:18

[18] The LORD is nigh unto them that are of a broken heart; and saveth such as be of a contrite spirit.

Matt. 6:7-8

[7] But when ye pray, use not vain repetitions, as the heathen do: for they think that they shall be heard for their much speaking.
[8] Be not ye therefore like unto them: for your Father knoweth what things ye have need of, before ye ask him.

1 Pet. 5:6-7

[6] Humble yourselves therefore under the mighty hand of God, that he may exalt you in due time:
[7] Casting all your care upon him; for he careth for you.

Psa. 147:1-5

[1] Praise ye the LORD: for it is good to sing praises unto our God; for it is pleasant; and praise is comely.
[2] The LORD doth build up Jerusalem: he gathereth together the outcasts of Israel.
[3] He healeth the broken in heart, and bindeth up their wounds.
[4] He telleth the number of the stars; he calleth them all by their names.
[5] Great is our Lord, and of great power: his understanding is infinite.