Very good question and the answer lyes in the New Testament 2nd Timothy 3:16"All scritpture is given by inspiration of God,and is profitable for doctrine,for for reproof, for correction, for instruction in righteousness:"So we use the whole bible not just the New or Old Testament.The reason I raise this question is there are mordern day churchs that will only use the New Testament and they can't understand certain things Jesus spoke of, the reason being they haven't studied the Old Testament.Notice Matthew5:5 "Blessed are the meek for they shall inherit the earth."What?If everyone ether goes to heaven or hell when they die ,who are the meek?The answer comes from the Old Testament Psalms 37:11'But the meek shall inherit the earth,:and shall delight themselves in the abundance of peace"Also Psalms 38:18 "The LORD knoweth the days of the upright:and their inhreritance shall be forever"The meek are a part of the righteous class not all of the righteous but part of it and the earth will be thiers forever in the future.Footnote to if Jesus is God ,Jesus is not God please look at this verse John 20:17"Jesus saith unto her,Touch me not;for I am not yet ascended to my Father: but go to my brethren,and say unto them.I ascend unto my Father and your Father:and to my God and your God". Jesus says my God and your God,now Jesus says his father is his God and his Father is our God so who is God?Jehovah! and Jesus tells us to only worship God Matthew 4:10.Very simple but Satan has confused mans thinking and once you learn the truth you see like at new born day at sunrise.....