Modern worship is often criticized for its plethora of what are labeled “7-11 songs” (songs which have seven words, sung eleven times). The criticism is that it is pointless, even stupefying, to say the same thing over and over again. But before all such songs are dismissed wholesale, let’s not throw the baby out with the bathwater.
First, the heavenly beings themselves incessantly chant “Holy, Holy, Holy…” over and over and over again before the throne of God (Revelation 4:8). (We might call that an "infinity-infinity song.")
Second, the Psalms themselves contain repetitions and refrains (cf. Psalms 8 & 136).
Third, the church has engaged in this practice since her inception (think of the repeated Kyrie Eleison [“Lord, Have Mercy”]).
Fourth, often times such “7-11 songs” are direct quotes of or strong allusions to Scripture, and when we are instructed to meditate on God’s Word (Psalm 1:2), what better way than singing and repetition?
There are of course ways where the repetition can be taken too far (and modern worship is guilty of this), but let’s remember that repetition is a biblical and historical church practice.