As I wrote in the piece "Hearing God's Voice": sincerity is necessary when praying/praying for others than yourself. Call it a basis that testifies of sincerity towards God and Christ before you can get started, so getting that basis in order is really necessary!
"Bondservants, obey in everything those who are your earthly masters, not by way of eye-service, as people-pleasers, but with sincerity (S 572) of heart, fearing the Lord", Col 3:22
"For our boast is this, the testimony of our conscience, that we behaved in the world with simplicity and godly sincerity (S 1515), not by earthly wisdom but by the Grace of God, and supremely so toward you.", 2 Cor 1:12
So sincerity is "a heart's desire" and therefore very personal. Not worldly or institutionally organized. And also not as the world sees or dictates it.
The word "sincerity" (Greek Haplotes; Strong 572) in Col 3:22 never goes with self-will/egoism or deceit. So not in or from sin.
The word "sincerity" in 2 Cor 1:12 (Greek Eilikrineia, Strong 1505) also does not accidentally mean "pure".
And that immediately tells something about the necessary basis for sincerity: not living from sin and not being in it!
Sin/sinning is doing your own will and thus placing yourself above God and the Commandments, so pretending that you are god yourself.
Sinning is therefore going against God's 10 Commandments (= the Law for Christians, 1John 3:4 + Rev 14:12+James 2:10-11) or going against a pure life (i.e. committing physical or spiritual fornication!), because that is what God requires of Christians. And yes: Christians can still sin as we also know from Hebrews 10:26 which says:
"If we have come to know the truth and still willfully and knowingly continue to sin, there is no longer any sacrifice that can take away our sins".
10 Commandments: God's Guidance needed
Sincerity for Christians therefore begins with knowing and living from God's 10 Commandments; including the 10th Commandment: keep the Sabbath holy; you do not work on it and you do not let others work (for you). Note: whoever breaks 1 Commandment, breaks all 10 Commandments (James 2:10-11) so you keep all 10. See also: 10 Commandments still valid!
However: it is God who wakes you up that you must keep the 10 Commandments so in fact it is God's Guidance that leads your heart in this (2Cor 1:12 "sincerity of God, not fleshly").
Christians must be baptized in Christ (alone) in order to be clean/pure in Christ. This is how you receive God's Grace for sins committed:
"Baptism has united you all to Christ; You have put on Christ as a garment. It no longer matters whether you are Jew or Greek, slave or free, male or female. For together you are one in Christ Jesus", Galatians 3:27-28.
"For God has reconciled the world to himself in Christ, not counting people's sins against them, and he has entrusted the message of reconciliation to us", 2Cor5:19.
Sincerity never ecclesiastical!
Churches are organized in a worldly way, have a pagan church belief in trinity, biunity or only in a god(head) and thus structurally violate Commandment 1 and 2 with Christ as a part-god or god-part instead of Lord/High Priest of God (Rom10:9/Hebr6:20). They often also violate the 4th Commandment and holy Sunday or a weekday instead of the Sabbath of God (Genesis 2:2-3) and of Christ (Matthew12:8) for example.
Churches & members/followers thus live in structural sin against all of God's Commandments. Better yet: they even teach that sinning is no longer possible, so that there is no longer any question of sincerity...
Ecclesiastical organization is also a worldly collective faith, not a personal matter of the heart.
Church faith is an unchristian false faith that is worldly and collective or impersonal and can never claim sincerity!
Does your heart cry out for purity, wanting to hear and follow God's Voice and Grace of God?! Then definitely look here and read the following:
1. How all churches are in Babylon
2. How to get out of church Babylon
3. Renewed acquaintance with God
4. Getting to know Christ better
Read all the links carefully; quality, authenticity and knowing which faith saves is really necessary. So be sincere in your actions and efforts there too!
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