1. first and the most important of all. You need to be a worshiper yourself.
2. second you need a revelation of the gospel.
3. third, you must know basic music, which anyone already has knowledge. if you can hum a tune. then thats it
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1. you need to be a worshiper
sure a musically and academically sound person can write worship song. even unbelievers can write songs.
but the song written by a worshiper cannot be compared.
in your quite time, make music to Jesus and for Jesus.
then the next thing you know you already have the music and lyrics in your heart.
2. you need a revelation of the gospel
have you heard the song "Amazing Grace" ?
this song speaks of the gospel.
write songs that points to Jesus. for example his death, sacrifice, love for you.
avoid writing songs something like "offering your life to God as a sacrifice"
rather, write song "acknowledging Jesus offered His life for you"
see the difference?
3. know basic music.
needless to say, if you can hum a tune, then thats it.
some years ago, i attended a workshop
the teacher said, if you can avail of a personal recorder, do so
there will be times when a melody is written in your heart, so grab that recorder and record the tune.
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on a side note... remember what Jesus said?
"Yet a time is coming and has now come when the true worshipers will worship the Father in the Spirit and in truth, for they are the kind of worshipers the Father seeks"
- John 4:23
you know what is worshiping in Spirit and in Truth?
see this verse
"For the law was given through Moses; grace and truth came through Jesus Christ."
- John 1:17
in the old testament, the Levites were priest and are in charge of worship and sacrifice offerings.
those were part of the the Law. there are instructions how to do offer the worship.
when Jesus died, the temple has become us. God dwells in us. the Holy Spirit lives in us.
unlike in the old testament, God dwells in the temple.
so worship in Spirit and in Truth means, worshiping by Grace.
ask Jesus for a revelation. write songs under this covenant.
i hope i gave you an idea...