This is what is known as (here's a 50-cent word) an "anthropomorphism": a fancy way of saying that God acts as if He were like a human being, in order for us to comprehend Him at all.

God is omniscient and He is out of time. Omniscience (since we are on the subject) is indicated in the following passages (KJV).

Note: Jesus had two nature: divine and human. In His human nature He did not know all things, but by virtue of His divine nature as God He did. I know, it is very confusing, but this is the orthodox Catholic theology of God or "theology proper," as it is called.

VI. JESUS IS OMNISCIENT (ALL-KNOWING)

A. God Alone is Omniscient

1) 1 SAMUEL 16:7 . . . {the Lord seeth} not as man seeth; for man looketh on the outward appearance, but the Lord looketh on the heart.

2) 1 KINGS 8:39 . . . give to every man according to his ways, whose heart thou knowest; (for thou, {even} thou only, knowest the hearts of all the children of men) {cf. 2 Chron 6:30}

3) 1 CHRONICLES 28:9 . . . the Lord searcheth all hearts, and understandeth all the imaginations of the thoughts: . . .

4) 2 CHRONICLES 16:9 For the eyes of the Lord run to and fro throughout the whole earth, to shew himself strong in the behalf of {them} whose heart {is} perfect toward him . . . {cf. Prov 15:3, Jer 32:19, Zech 4:10}

5) JOB 34:21 For his eyes {are} upon the ways of man, and he seeth all his goings.

6) JOB 37:16 Dost thou know the balancings of the clouds, the wondrous works of him which is perfect in knowledge? {cf. Job 36:4}

7) JOB 42:2 . . . no thought can be withholden from thee.

8) PSALM 44:21 Shall not God search this out? for he knoweth the secrets of the heart.

9) PSALM 147:5 Great {is} our Lord, and of great power: his understanding {is} infinite.

10) PROVERBS 21:30 {There is} no wisdom nor understanding nor counsel against the Lord.

11) ISAIAH 40:28 . . . the Creator of the ends of the earth, . . . {there is} no searching of his understanding.

12) ISAIAH 46:10 Declaring the end from the beginning, and from ancient times {the things} that are not {yet} done, saying, My counsel shall stand, and I will do all my pleasure:

13) ISAIAH 48:3-6 I have declared the former things from the beginning; and they went forth out of my mouth, and I shewed them; I did {them} suddenly, and they came to pass. (4) Because I knew that thou {art} obstinate, and thy neck {is} an iron sinew, and thy brow brass; (5) I have even from the beginning declared {it} to thee; before it came to pass I shewed {it} thee: lest thou shouldest say, Mine idol hath done them, and my graven image, and my molten image, hath commanded them. (6) Thou hast heard, see all this; and will not ye declare {it}? I have shewed thee new things from this time, even hidden things, and thou didst not know them.

14) ISAIAH 66:18 For I {know} their works and their thoughts: . . .{cf. 1 Cor 3:20}

15) EZEKIEL 11:5 . . . Thus saith the Lord; Thus have ye said, O house of Israel: for I know the things that come into your mind, {every one of} them.

16) MATTHEW 6:8 . . . your Father knoweth what things ye have need of, before ye ask him.

17) MATTHEW 6:18 . . . thy Father, which seeth in secret, shall reward thee openly. {cf. 6:32}

18) LUKE 16:15 . . . God knoweth your hearts: for that which is highly esteemed among men is abomination in the sight of God.

19) ACTS 1:24 And they prayed, and said, Thou, Lord, which knowest the hearts of all {men}, shew whether of these two thou hast chosen, {cf. 15:8}

20) ACTS 15:18 Known unto God are all his works from the beginning of the world.

21) ROMANS 8:27 And he that searcheth the hearts knoweth what {is} the mind of the Spirit, . .

22) ROMANS 11:33-34 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! (34) For who hath known the mind of the Lord? or who hath been his counseller?

23) HEBREWS 4:13 Neither is there any creature that is not manifest in his sight: but all things {are} naked and opened unto the eyes of him with whom we have to do.

24) 1 JOHN 3:20 God . . . knoweth all things.

B. Indications in Jesus' Own Words

1) MATTHEW 9:4 And Jesus knowing their thoughts said, Wherefore think ye evil in your hearts?

2) MATTHEW 22:18 But Jesus perceived their wickedness, and said, Why tempt ye me, {ye} hypocrites?

3) MATTHEW 26:46 Rise, let us be going: behold, he is at hand that doth betray me. {cf. Mk 14:42}

4) MARK 2:8 And immediately when Jesus perceived in his spirit that they so reasoned within themselves, he said unto them, Why reason ye these things in your hearts? {cf. Lk 5:22}

5) MARK 5:30 And Jesus, immediately knowing in himself that virtue had gone out of him, turned him about in the press, and said, Who touched my clothes?

6) LUKE 22:10-13 And he said unto them, Behold, when ye are entered into the city, there shall a man meet you, bearing a pitcher of water; follow him into the house where he entereth in. (11) And ye shall say unto the goodman of the house, The Master saith unto thee, Where is the guestchamber, where I shall eat the passover with my disciples? (12) And he shall shew you a large upper room furnished: there make ready. (13) And they went, and found as he had said unto them: and they made ready the passover. {cf. Mk 14:13-15}

7) JOHN 5:42 But I know you, that ye have not the love of God in you.

8) JOHN 6:64 But there are some of you that believe not. For Jesus knew from the beginning who they were that believed not, and who should betray him.

9) JOHN 13:10-11 . . . ye are clean, but not all. (11) For he knew who should betray him; therefore said he, Ye are not all clean.

{Additionally, there are many other verses illustrating that Jesus knew the future perfectly (e.g., Mt 12:40, 16:21, 17:9,11-12,22-23, 20:18-19, 21:39, 24:2, 26:2,12,21,31-34,54 Mk 8:31, 9:31, 10:32-34, 14:9,18,27-30,42,49, Lk 9:22,44, 11:30, 12:50, 17:25, 18:31-33, 22:15,21-22,32,34,37, Jn 2:19, 3:14, 10:11,15,17-18, 12:32-34, 13:18-21, 14:19, 15:13, 16:20, 18:11, 21:18-19}

C. N.T. Apostolic Witness

1) MATTHEW 12:25 And Jesus knew their thoughts, . . .

2) MATTHEW 13:54 . . . he taught them in their synagogue, insomuch that they were astonished, and said, Whence hath this {man} this wisdom, and {these} mighty works?

3) LUKE 2:47 And all that heard him were astonished at his understanding and answers.

4) LUKE 6:8 But he knew their thoughts, . . .

5) LUKE 9:47 And Jesus, perceiving the thought of their heart, . . .

6) JOHN 2:24-25 But Jesus did not commit himself unto them, because he knew all {men}, (25) And needed not that any should testify of man: for he knew what was in man.

7) JOHN 4:29 Come, see a man, which told me all things that ever I did: is not this the Christ? {cf. 4:17-19}

8) JOHN 7:15 And the Jews marvelled, saying, How knoweth this man letters, having never learned?

9) JOHN 13:1 Jesus knew that his hour was come that he should depart out of this world unto the Father, . . .

10) JOHN 16:30 Now are we sure that thou knowest all things, and needest not that any man should ask thee: by this we believe that thou camest forth from God.

11) JOHN 18:4 Jesus therefore, knowing all things that should come upon him, . . .

12) JOHN 21:17 . . . Lord, thou knowest all things; thou knowest that I love thee . . .

13) COLOSSIANS 2:3 In whom are hid all the treasures of wisdom and knowledge.

14) REVELATION 2:23 . . . I am he which searcheth the reins and hearts: . . .