Some preachers speak of a difference between the "God" of the Old Testament and the "God" of the New Testament, as if God has changed.
These preachers disregard scriptures such as:
Galatians 6:7-8 Be not deceived; God is not mocked: for whatsoever a man soweth, that shall he also reap. For he that soweth to his flesh shall of the flesh reap corruption; but he that soweth to the Spirit shall of the Spirit reap life everlasting.
II Corinthians 5:9-11 Wherefore we labour, that, whether present or absent, we may be accepted of Him.
For we must all appear before the judgment seat of Christ; that every one may receive the things done in his body, according to that he hath done, whether it be good or bad. Knowing therefore the terror of the Lord, we persuade men;
I Corinthians 6:9-10 Know ye not that the unrighteous shall not inherit the kingdom of God? Be not deceived: neither fornicators, nor idolaters, nor adulterers, nor effeminate, nor abusers of themselves with mankind, Nor thieves, nor covetous, nor drunkards, nor revilers, nor extortioners, shall inherit the kingdom of God.
And in the book of Revelation, we read of that great tribulation, the 14 plagues God will send upon this present earth in the last days before Jesus returns.
Revelation 8
6 And the seven angels which had the seven trumpets prepared themselves to sound.7 The first angel sounded, and there followed hail and fire mingled with blood, and they were cast upon the earth: and the third part of trees was burnt up, and all green grass was burnt up.
8 And the second angel sounded, and as it were a great mountain burning with fire was cast into the sea: and the third part of the sea became blood; 9 And the third part of the creatures which were in the sea, and had life, died; and the third part of the ships were destroyed.
10 And the third angel sounded, and there fell a great star from heaven, burning as it were a lamp, and it fell upon the third part of the rivers, and upon the fountains of waters; 11And the name of the star is called Wormwood: and the third part of the waters became wormwood; and many men died of the waters, because they were made bitter.
12 And the fourth angel sounded, and the third part of the sun was smitten, and the third part of the moon, and the third part of the stars; so as the third part of them was darkened, and the day shone not for a third part of it, and the night likewise.
30 And then shall appear the sign of the Son of man in heaven: and then shall all the tribes of the earth mourn, and they shall see the Son of man coming in the clouds of heaven with power and great glory.
31 And HE shall send His angels with a great sound of a trumpet, and they shall gather together His elect from the four winds, from one end of heaven to the other.
10 But the day of the Lord will come as a thief in the night; in the which the heavens shall pass away with a great noise, and the elements shall melt with fervent heat, the earth also and the works that are therein shall be burned up.
11 Seeing then that all these things shall be dissolved, what manner of persons ought ye to be in all holy conversation and godliness,
12 Looking for and hasting unto the coming of the day of God, wherein the heavens being on fire shall be dissolved, and the elements shall melt with fervent heat?
13 Nevertheless we, according to His promise, look for new heavens and a new earth, wherein dwelleth righteousness.
14 Wherefore, beloved, seeing that ye look for such things, be diligent that ye may be found of Him in peace, without spot, and blameless.
2 And I John saw the holy city, new Jerusalem, coming down from God out of heaven, prepared as a bride adorned for her husband.
3 And I heard a great voice out of heaven saying, Behold, the tabernacle of God is with men, and HE will dwell with them, and they shall be HIS people, and God Himself shall be with them, and be their God.
4 And God shall wipe away all tears from their eyes; and there shall be no more death, neither sorrow, nor crying, neither shall there be any more pain: for the former things are passed away.
5 And HE that sat upon the throne said, Behold, I make all things new.