I understand which verses talk about singing, but the main verse used by the churches of Christ to back up their singing is found in Ephesians. However, the verses prior to and after do not imply anything about worship. The prior verse speaks of not being drunk from wine wherein is excess. Did the wine have alcohol in it? If it didn't you could not be drunk if you had drank to excess. Does the verse speaking about greeting one another in spiritual songs, psalms and singing to one another even remotely mention worship? We also are not to add personal opinions where the Scriptures are concerned. Each person who has the ability to read the Bible should and never take a person's word without checking it for themselves in the Holy Word. How many times do we greet each other in songs and psalms? I have yet to see it. We meet in church every service and sing but not to each other. So is everyone sinning when they see another believer and do not immediately start singing and speaking in psalms whether on the street or in church on Sunday? Tell me where it is written in the Holy Bible that the singing and making melody in the heart is referencing worship only. I would really like to know. There is another often used verse which is almost identical; however, it does not say make melody in the heart.
"See then that you walk circumspectly, not as fools but as wise, redeeming the time, because the days are evil. Therefore do not be unwise, but understand what the will of the Lord is. And do not be drunk with wine, in which is dissipation; but be filled with the Spirit, speaking to one another in psalms and hymns and spiritual songs, singing and making melody in your heart to the Lord, giving thanks always for all things to God the Father in the name of our Lord Jesus Christ, submitting to one another in the fear of God" (Ephesians 5:15-21).
It is best to begin a discussion by looking at the actual verses instead of attempting to allude to them.
Two states are being contrasted in Ephesians 5:18, being filled with wine and being filled with the Spirit. The point of the contrast is that you cannot have both at once -- they are mutually exclusive. You cannot be partially filled with spirits and partially filled with the Spirit. Similar exclusions appear in Luke 1:15 and Acts 2:4, 15. In other words, the indwelling of the Spirit is connected with the abstinence of liquor.
The clause that literally reads "in which is debauchery" refers to wine in Ephesians 5:18. Some translations change it to "that is debauchery" meaning getting drunk is debauchery, but this is not what the original text states. The original text states that there is debauchery in wine, as in Proverbs 23:31. In a letter to Laeta, a lady who wrote asking how to bring up her infant daughter, Jerome advised, "Let her learn even now not to drink wine 'wherein is excess.'" This quote of Ephesians 5:18 shows that Jerome believed the excess referred to the wine and not that drunkenness held excess. Albert Barnes stated, "Let Christians when about to indulge in a glass of wine, think of this admonition [Ephesians 5:18]. Let them remember that their bodies should be the temple of the Holy Ghost rather than a receptacle for intoxicating drinks. Was any man ever made a better Christian by the use of wine? Was any minister ever better fitted to counsel an anxious sinner, or to pray, or to preach the gospel, by the use of intoxicating drinks? Let the history of wine-drinking and intemperate clergymen answer." [See the article "New Testament Beverages" for further information.]
The key points in the verses leading up to Ephesians 5:19 is that because of the evil days approaching Christians need to use their minds. Such requires learning and understanding God's will to the point that they are filled with the teaching of the Spirit. Ephesians 5:19 continues the points by encouraging Christians to teach each other in their songs while giving thanks to God.
How do we know that Paul is speaking of worship? The speaking in psalms, hymns, and spiritual songs is directed to the Lord and is done so to give thanks to God. Worship is doing those things which gives praise and honor to God in a manner prescribed by God and with a proper attitude focused on God (John 4:21-24). All parts of the definition of worship are demonstrated in this passage, thus the inescapable conclusion is that we are talking about worship. [See the lesson "What is Worship?" for further information.]
I noted that you altered the wording of Ephesians 5:19 by changing "speaking" to "greeting" and then made a ridiculously elaborate argument based on the altered wording.
Please also note that while the singing in Ephesians 5:19 is referring to the worship of God, I have made no statement that all singing is only worship. The insertion of "only" in your argument was done to bolster a weak position.
The other passage that you alluded to is "Let the word of Christ dwell in you richly in all wisdom, teaching and admonishing one another in psalms and hymns and spiritual songs, singing with grace in your hearts to the Lord. And whatever you do in word or deed, do all in the name of the Lord Jesus, giving thanks to God the Father through Him" (Colossians 3:16-17). The same basic points are being made in this passage as was made in Ephesians. It too contains all the elements of constitutes worship and thus is understood to be discussing worship.