Being pure is not complete without His word and His grace
Being pure is essential in serving God but when we took it literally it is different already.
When we were still enemy of God, we were not pure in front of Him because of the sin we committed that broke his heart. still he made a way for us to become pure again and sent his son for us to become new again and to have an everlasting life. he has given us the chance of second purity.
The Puritans were believing that they can please God if they are pure in every way. and in applying it in the church it is very helpful because we can say that we are not guilty in from of God and men when we work in our ministries. and it is also helpful for the worker himself because it gives harmony in everything he does. But still it should done in biblical way not just making himself pure in his work just to please others but it should be glorifying to God.
And when we apply being a puritan in the aspects of our worship to God in a biblical sound way. It is very aromatic to God because we are worshiping him in all that we are without blemish yet we are still human so this cannot be applied into our lives without the grace of God. We cannot do anything apart Him. We can only be without blemish when the times come that we are going to have a fellowship with God in heaven, someday.