Andy Chamberlain offers a few ideas that’ll help you make songs more usable:
They are in the wrong key for your congregation. Let’s start with the single biggest reason why your congregation won’t be able to sing an ‘original’ version. Album and even definitive live versions of worship songs are arranged in keys that suit the lead singer’s or the artist’s voice, NOT the congregation’s range. Albums have to be great to listen to and the vocal has to be the strongest it can be, therefore from a listening perspective it has to be in the artist’s strongest key, which 9 times out of 10 isn’t the most suitable key for a congregation because the key needs to be a compromise between stereotypical male and female vocal ranges. Broadly speaking, songs with male vocals are often 2-3 semi tones too high and songs with female vocals are (less) often 2 semi tones too low.
Octave jumps simply don’t work. Octave jumps are great tools to make songs dynamically exciting. They work great for radio where you need a big lift to keep the listener interested, BUT, whenever a song has an octave leap you alienate one or other gender in your congregation and 50% of them will either stop singing or sound like they’ve inhaled a helium balloon. So, if you genuinely want to encourage participation, don’t do octave leaps. That will probably mean moving the key down a minor or major third, but if you want more participation make it more singable for more people, more of the time.
Intros are too long. There are lots of worship songs with 8, 16 or even 32 bar intros that build a sense of dynamic anticipation. These can work at huge conferences and worship concerts but let’s remember the entire point of congregational worship is maximum congregational involvement. If they have to wait around while the band enjoys a long intro they will disengage. Then the intro really becomes much more about the band’s enjoyment rather than the congregation’s participation. Try to make intros as succinct as possible just to establish the tempo, groove and where to come in. So most of the time 2 or 4 bars is plenty.