I’m looking for answers from Protestant Trinitarians as this seems to be a fairly recent explanation, currently in vogue in some groups (mainly evangelical, I would suppose).
The basis for my query is the following scripture texts (all A.V.):
“And not only so, but we also joy in God through our Lord Jesus Christ, by whom we have now received the atonement.” Romans 5:11
“And Aaron shall make an atonement upon the horns of it once in a year with the blood of the sin offering of atonements: once in the year shall he make atonement upon it throughout your generations : it is most holy unto the Lord. …when they give an offering unto the Lord, to make an atonement for your souls, and thou shalt take the atonement money of the children of Israel, and shalt appoint if for the service of the tabernacle of the congregation; that it may be a memorial unto the children of Israel before the Lord, to make an atonement for your souls.” Exodus 30:10 & 15-16
“For the life of the flesh is in the blood : and I have given it to you upon the altar to make an atonement for your soul : for it is the blood that maketh an atonement for the soul.” Leviticus 17:11
I note that modern translations use the word ‘atonement’ more frequently. However, I am not looking for simple agreement with what those texts say, or any subjective opinion as to what atonement means to individual Christians, but of what this one word, ‘atonement’ actually means, in context, and whether it could be misleading to say it means ‘at-one-ment’ (not least because that phrase of cobbled-together words explains nothing, in and of itself.)