The phrase "word of the Lord" is a phrase that is often used to to designate NT truth that was the teaching of Jesus Christ and was a matter of NT doctrines not necessarily established in the OT. Look here.<sigh>
Only a heretic would try to use Paul as an excuse to reject the teachings of Jesus.
And they, when they had testified and preached the word of the Lord, returned to Jerusalem, and preached the gospel in many villages of the Samaritans.
Then remembered I the word of the Lord, how that he said, John indeed baptized with water; but ye shall be baptized with the Holy Ghost.
It is in our text we have been discussing on another thread.
And when the Gentiles heard this, they were glad, and glorified the word of the Lord: and as many as were ordained to eternal life believed.
Certainly you would not read of gentiles on equal standing with Jews in the OT.
The word of the Lord is the OT designation for Jesus Christ. It is first used in the beginning of the third millennium of human history in Ge 15 and he appeared in a vision to Abraham. For the first time he is given the name in scripture as "Lord GOD." This is Adonay Jehovah . This is a critical pivot point in the progressive revelation of God and his unfolding drama of redemption. It is needful for us to know this in our understanding of the trinitarian work of God in salvation. Often times the word of the Lord comes to the prophets of Israel as a Christophany, but not always. Here is a passage where this designation is very important.
The LORD (Jehovah) said unto my Lord (Adonay), Sit thou at my right hand, until I make thine enemies thy footstool.
The word of the LORD of the OT is the same word of the Lord in the NT and he is the Lord GOD.
Here is just a bit of extra information for you to ponder in this context.
5 Defraud ye not one the other, except it be with consent for a time, that ye may give yourselves to fasting and prayer; and come together again, that Satan tempt you not for your incontinency.
6 But I speak this by permission, and not of commandment.
7 For I would that all men were even as I myself. But every man hath his proper gift of God, one after this manner, and another after that.
8 I say therefore to the unmarried and widows, it is good for them if they abide even as I.
9 But if they cannot contain, let them marry: for it is better to marry than to burn.
10 And unto the married I command, yet not I, but the Lord, Let not the wife depart from her husband:
11 But and if she depart, let her remain unmarried or be reconciled to her husband: and let not the husband put away his wife.
12 But to the rest speak I, not the Lord: If any brother hath a wife that believeth not, and she be pleased to dwell with him, let him not put her away.
This is another subject but it will help to study this out.
Gen 15:1 After these things the word of the LORD came unto Abram in a vision, saying, Fear not, Abram: I am thy shield, and thy exceeding great reward.
2 And Abram said, Lord GOD, what wilt thou give me, seeing I go childless, and the steward of my house is this Eliezer of Damascus?
3 And Abram said, Behold, to me thou hast given no seed: and, lo, one born in my house is mine heir.
4 And, behold, the word of the Lord came unto him, saying, This shall not be thine heir; but he that shall come forth out of thine own bowels shall be thine heir.
the word of the Lord = Lord GOD = manifest so as to be seen " in a vision,"
I am not a heretic as you claim. I am a person who believes the words.
Here is my advice to you. Believe the words and search out context.