Praise the Lord. Praise the name of the Lord; praise him, you servants of the Lord, you who minister in the house of the Lord, in the courts of the house of our God. Praise the Lord, for the Lord is good; sing praise to his name, for that is pleasant. Psalm 135:1-3 (NIV)Self-consciousness can be the enemy of true worship. It is stirred naturally in the repentance phase as a consequence of the light of God, but it is not a condition the worshipper can stay in and proceed with worship. Our gaze must rise to look upon God thereafter. Worship is, after all, a God-conscious thing.
Some folk feel very self-consciousness in public, and if so, singing in a congregational setting (particularly if it is small) can be a non-starter. However, part of being a true worshipper, the kind that God seeks, is getting beyond ourselves, our nervousness and self-consciousness, to focus ourselves on God and sing. Even the self-conscious, self-admittedly bad singer, even the non-singer, will end up being a singer if they come into the presence of God to worship. When all is said and done, the likelihood is that the experience, if followed to it's ultimate conclusion, will have been found to have been exhilarating.
And there really is no way out of this, it is a biblical mandate. Within the Bible's book of songs (Psalms), there are 70 references (at least) either calling on believers to sing or referring to it as an appropriate response to God. There are several in the New Testament too, as well as the recording of incidences in which key figures sang before God. Jesus and the disciples sang hymns; Paul and Silas sang praise to God; angels sing around the throne of God; and people that have been welcomed into God's presence sing.
Let's be honest, it is not like singing should be that difficult for us. We sing at birthdays, we sing in the shower, we sing driving the car, we sing at ballgames, even drunks sing! But whereas we are never to be drunk, we are most certainly to sing!
"Do not get drunk on wine, which leads to debauchery. Instead, be filled with the Spirit, speaking to one another with psalms, hymns, and songs from the Spirit. Sing and make music from your heart to the Lord, always giving thanks to God the Father for everything, in the name of our Lord Jesus Christ." Ephesians 5:18-20 (NIV)Singing is just something the saved do--singing is part of being in the breath (Spirit) of God.
Now, there are two basic biblical varieties of singing in worship (with one variety having two further subcategories). We sing with the mind and we sing with the Spirit (i.e. in tongues). Singing with the mind is further subdivided into songs that are already known, that is previously composed, and spontaneous songs (new) which are improvised. Every song sung in the Spirit (tongues) is a new song.
So, the worship of God is going to be a singing affair. Some of the songs sung will be planned, some will be spontaneous. Singing isn't the only aspect of worship, but there is no avoiding singing as part of worship. Singing in worship is not about us, it's about God--a vehicle through which God-consciousness can be expressed in the worshipping believer.
We'll be singing in the presence of God throughout eternity. The good news is that we can enter into that heavenly occupation now!