faith--> assurance

But needs action which leads to evidence.

testament (n.)

Late Latin testamentum in this case was a confusion of the two meanings of Greek diatheke, which meant both "covenant, dispensation" and "will, testament," and was used in the former sense in the account of the Last Supper (see testimony) but subsequently was interpreted as Christ's "last will."

What is the original Roman meaning of the word sacrament?

a soldier's oath of allegiance

In Ancient Rome, the term meant a soldier's oath of allegiance. Tertullian, a 3rd-century Christian writer, suggested that just as the soldier's oath was a sign of the beginning of a new life, so too was initiation into the Christian community through baptism and Eucharist.