There are many passages in the New Testament that refer to Jesus as Lord. “Lord,” in these contexts, is a reference to His deity, as is made clear by the texts below. In each of the passages below, the phrase “Lord” is used to refer both to Christ, and also to the Old Testament God. I have highlighted the use of Lord so that you can find it easily in each passage:
that if you confess with your mouth the Lord Jesus and believe in your heart that God has raised Him from the dead, you will be saved. 10 For with the heart one believes unto righteousness, and with the mouth confession is made unto salvation. 11 For the Scripture says, “Whoever believes on Him will not be put to shame.”[f] 12 For there is no distinction between Jew and Greek, for the same Lord over all is rich to all who call upon Him. 13 For “whoever calls on the name of the Lord shall be saved.” (Romans 10:9-12)
In this next passage, the Old Testament idea of the “Day of the Lord” (Day of God’s Judgment) is used in the same passage where Jesus is frequently referred to as Lord. This clearly teaches that Jesus is the Old Testament God:
But the day of the Lord will come as a thief in the night, in which the heavens will pass away with a great noise, and the elements will melt with fervent heat; both the earth and the works that are in it will be burned up.[c] 11 Therefore, since all these things will be dissolved, what manner of persons ought you to be in holy conduct and godliness, 12 looking for and hastening the coming of the day of God, because of which the heavens will be dissolved, being on fire, and the elements will melt with fervent heat? 13 Nevertheless we, according to His promise, look for new heavens and a new earth in which righteousness dwells.
14 Therefore, beloved, looking forward to these things, be diligent to be found by Him in peace, without spot and blameless; 15 and consider that the longsuffering of our Lord is salvation—as also our beloved brother Paul, according to the wisdom given to him, has written to you, 16 as also in all his epistles, speaking in them of these things, in which are some things hard to understand, which untaught and unstable people twist to their own destruction, as they do also the rest of the Scriptures.
17 You therefore, beloved, since you know this beforehand, beware lest you also fall from your own steadfastness, being led away with the error of the wicked;18 but grow in the grace and knowledge of our Lord and Savior Jesus Christ.
To Him be the glory both now and forever. Amen. (II Peter 3:14-18)
The Apostle Peter also uses the title “Lord” in the same way that Peter does, in his reference to the day of the Lord in I Thessalonians:
But concerning the times and the seasons, brethren, you have no need that I should write to you. 2 For you yourselves know perfectly that the day of the Lord so comes as a thief in the night. 3 For when they say, “Peace and safety!” then sudden destruction comes upon them, as labor pains upon a pregnant woman. And they shall not escape. 4 But you, brethren, are not in darkness, so that this Day should overtake you as a thief. 5 You are all sons of light and sons of the day. We are not of the night nor of darkness. 6 Therefore let us not sleep, as others do, but let us watch and be sober. 7 For those who sleep, sleep at night, and those who get drunk are drunk at night. 8 But let us who are of the day be sober, putting on the breastplate of faith and love, and as a helmet the hope of salvation. 9 For God did not appoint us to wrath, but to obtain salvation through our Lord Jesus Christ, 10 who died for us, that whether we wake or sleep, we should live together with Him. (I Thessalonians 5:1-10)
These are just a handful of the passages that clearly equate the Lord Jesus Christ with the Lord of the Old Testament. There are dozens of other “Lord” passages that clearly indicate Christ’s deity as well. Anybody who is honestly interested in learning what the Bible really teaches about Jesus would be well advised to study them closely.