The following depends heavily on the covenant theology evidenced by Hebrews 6:4-9, especially certain reflections on vv. 8 and 9 which will not be spelled out here in detail.
Definitions
Covenant privilege: those benefits that accrue to all baptized members of a true Christian church, irrespective of their perseverance in the life of the church, or final salvation
Salvation: those benefits that begin to accrue to every elect person at the time of their effectual calling, which unites them to Christ in a full, everlasting sense; these benefits include personal regeneration, individual justification by faith, adoption as sons, the indwelling of the Holy Spirit, spiritual gifting, definitive personal sanctification leading to progressive sanctification, unto glorification at the Last Day
Judgments of charity: assuming the best about fellow Christians who are members in good standing in faithful Christian churches
Theses
1) Salvation is not ordinarily found outside the sphere of formal covenant privilege in the context of the visible church
2) Salvation must be distinguished from mere covenant privilege, the former concept encompassing more than the latter
3) Salvation is received by saving faith, and cannot be lost, because of the Spirit's preserving power
4) Covenant privilege is received by all persons baptized in a true Christian church, by means of baptism (though children and the spouse of one believer are initially "holy" in a sense even before the baptismal ceremony)
5) Covenant privilege may be lost by apostasy (defined as definitively turning away from Christ and the life of the church, after continuing for a time even in some kind of "faith"), or by death in the case of a flagrant hypocrite whose hypocrisy is not discovered by church discipline in the course of his or her life
6) Covenant privilege involves certain objective blessings of visible church membership, but also involves, subjectively, potential blessing and potential cursing--cursing more severe than either the sanctions of the covenant of works alone or of the Mosaic covenant, upon apostasy
7) Baptism is an effectual means of covenant privilege for all persons baptized in true churches, but is also an effectual means of salvation for the elect whom the Spirit personally regenerates (though this regeneration does not necessarily occur at the time of the administration of baptism)
8) Judgment of charity involves not only recognition of the fact of covenant privilege belonging to other baptized church members, but a presumption of the full salvation of every other covenant member
9) Covenant privilege entitles a church member to a judgment of charity on the part of all fellow church members, until such time as church discipline is carried out by church officers to the point of excommunication.
10) Beyond judgments of charity toward all recipients of covenant privilege through baptism and church membership, personal and communal assurance of salvation may be strengthened through the (fallible) observance of the presence of fruits of the Spirit, which distinguishes true, saving faith from demonic "faith" like the Jews' initial faith in John 8:31ff
