Jesus trusted the Scriptures. He often referred to them and repeated "written is ..". (Matt.4:4,7,10,21:13)
Why don’t we as Christens and his followers always trust in Old testament.

"Now all this was done, that it might be fulfilled which was spoken of the Lord by the prophet. (Matt.1:22)
(See also Matt. 2:15, 17, 23, 8:17)

But from the beginning of the creation God made them male and female. (Mark.10:6) Not after millions of years.

That the blood of all the prophets, which was shed from the foundation of the world, may be required of this generation; 51. From the blood of Abel unto the blood of Zacharias which perished between the altar and the temple: verily I say unto you, It shall be required of this generation. (Luke 11:50-51. See also Matt. 23:35)

37. But as the days of Noe were, so shall also the coming of the Son of man be.

38. For as in the days that were before the flood they were eating and drinking, marrying and giving in marriage, until the day that Noe entered into the ark, 39. And knew not until the flood came, and took them all away; so shall also the coming of the Son of man be. (Matt.24:37-39)

But into whatsoever city ye enter, and they receive you not, go your ways out into the streets of the same, and say, … that it shall be more tolerable in that day for Sodom, than for that city. (Luke 10:10…12)

Likewise also as it was in the days of Lot; they did eat, they drank, they bought, they sold, they planted, they builded; 29. But the same day that Lot went out of Sodom it rained fire and brimstone from heaven, and destroyed them all. 30. Even thus shall it be in the day when the Son of man is revealed. 31. In that day, he which shall be upon the housetop, and his stuff in the house, let him not come down to take it away: and he that is in the field, let him likewise not return back. 32. Remember Lot's wife. (Luke 17:28-32)

But as touching the resurrection of the dead, have ye not read that which was spoken unto you by God, saying, 32. I am the God of Abraham, and the God of Isaac, and the God of Jacob? God is not the God of the dead, but of the living. (Matt.22:31-32)

39. They answered and said unto him, Abraham is our father. Jesus saith unto them, If ye were Abraham's children, ye would do the works of Abraham. 40. But now ye seek to kill me, a man that hath told you the truth, which I have heard of God: this did not Abraham. … 56. Your father Abraham rejoiced to see my day: and he saw it, and was glad. 57. Then said the Jews unto him, Thou art not yet fifty years old, and hast thou seen Abraham? 58. Jesus said unto them, Verily, verily, I say unto you, Before Abraham was, I am. (Joh.8:39-40, 56-58)

Do not think that I will accuse you to the Father: there is one that accuseth you, even Moses, in whom ye trust. 46. For had ye believed Moses, ye would have believed me; for he wrote of me. (Joh.5:46-47)

Did not Moses give you the law, and yet none of you keepeth the law? Why go ye about to kill me? (Joh.7:19)

The story about the rich man and Lazarus : Abraham saith unto him, They have Moses and the prophets; let them hear them. 30. And he said, Nay, father Abraham: but if one went unto them from the dead, they will repent. 31. And he said unto him, If they hear not Moses and the prophets, neither will they be persuaded, though one rose from the dead. (Luke 16:29-31)

And Jesus answered and said, while he taught in the temple, How say the scribes that Christ is the son of David? 36. For David himself said by the Holy Ghost, The LORD said to my Lord, Sit thou on my right hand, till I make thine enemies thy footstool. (Mark 12:35-37)

Have ye not read what David did, when he was an hungred, and they that were with him; (Matt.12:3)

And in them is fulfilled the prophecy of Esaias, which saith, By hearing ye shall hear, and shall not understand; and seeing ye shall see, and shall not perceive: 15. For this people's heart is waxed gross, and their ears are dull of hearing, and their eyes they have closed; lest at any time they should see with their eyes and hear with their ears, and should understand with their heart, and should be converted, and I should heal them. (Matt.13:14-15, etc)

But he answered and said unto them, An evil and adulterous generation seeketh after a sign; and there shall no sign be given to it, but the sign of the prophet Jonas: 40. For as Jonas was three days and three nights in the whale's belly; so shall the Son of man be three days and three nights in the heart of the earth. 41. The men of Nineveh shall rise in judgment with this generation, and shall condemn it: because they repented at the preaching of Jonas; and, behold, a greater than Jonas is here. (Matt.12:39-41)

When ye therefore shall see the abomination of desolation, spoken of by Daniel the prophet, stand in the holy place, (whoso readeth, let him understand:) (Matt.24:15)

The Son of man indeed goeth, as it is written of him: but woe to that man by whom the Son of man is betrayed! good were it for that man if he had never been born. (Mark 14:21)

Then he said unto them, O fools, and slow of heart to believe all that the prophets have spoken: 26. Ought not Christ to have suffered these things, and to enter into his glory? 27. And beginning at Moses and all the prophets, he expounded unto them in all the scriptures the things concerning himself. (Luke 24:25-27)

Think not that I am come to destroy the law, or the prophets: I am not come to destroy, but to fulfil. 18. For verily I say unto you, Till heaven and earth pass, one jot or one tittle shall in no wise pass from the law, till all be fulfilled. (Matt.5:17-18)

Heaven and earth shall pass away: but my words shall not pass away. (Luke 21:33)

and the scripture cannot be broken; (Joh.10:35)