Faith is the result and effect of Grace, the Grace of regeneration, a true believer believes BECAUSE OF GRACE Acts 18:27
27 And when he was disposed to pass into Achaia, the brethren wrote, exhorting the disciples to receive him: who, when he was come, helped
them much which had believed through grace:
The word through here is the prep dia:
- the ground or reason by which something is or is not done
- by reason of
- on account of
- because of for this reason
- therefore
- on this account
A Person is saved by Grace and then believe, Grace here in Acts 18:27 is regeneration by the Spirit, the Spirit of Grace.