Many people have difficulty with words like church, religion, and worship because they have acquired negative connotations through association with evangelicalism and fundamentalism. As Dennis Potter once said, "The trouble with words is that they've been in other people's mouths."
So I would like to suggest some more positive meanings for these words.
Religion - to reconnect with all that is; to connect with one's deeper being in community with others.
Church - a community of people with whom one goes on a spiritual quest or journey.
Worship - a celebration of what is of ultimate worth in our lives
Belief - trusting and loving something greater than yourself (not necessarily something supernatural - it could be humanity or your community)
Faith - a state of openness or trust
God - the experience of connection with other beings, the ultimate mystery, the source of all life, the spirit of life, the ground of all being
Some words might be irredeemable... but let's give them a try:
Christian - someone who follows the teachings of Jesus and tries to live by his values
Salvation - a process of healing and restoring the lost parts of the soul to each other (not undertaken by some strange supernatural means, but by being in loving community with others)
Sin - a state of alienation or separation from the wellsprings of life
The trouble with using these words without carefully qualifying of what you're talking about is that people will hear the original meaning of the word that they were taught, rather than the (new to them) liberal meaning - especially in a culture where people are more interested in the dictionary definition (denotation) of a word than how it is used in different contexts (connotation). So if you're going to use one of these words to mean something other than the accepted view of what it means, it can cause difficulty to newcomers to your liberal religious community.