The gospel is very simple, Paul details the true pure Gospel of Jesus Christ in 1 Corinthians 15:
“1 Now I would remind you, brothers, of the gospel I preached to you, which you received, in which you stand, 2 and by which you are being saved, if you hold fast to the word I preached to you—unless you believed in vain.
3 For I delivered to you as of first importance what I also received: that Christ died for our sins in accordance with the Scriptures, 4 that he was buried, that he was raised on the third day in accordance with the Scriptures” 1 Cor 15:1-4 ESV
We are not to add to this and we are certainly not to contradict it (Gal 1:8). That said, sometimes we do have to take a page out of Pauls book and meet people where they are at like he did the Greeks on Mars Hill (Acts 17:22-34). When I share the gospel with SDA I have found it helps to contrast it with the false SDA gospel so that they can see the difference for themselves.
In person I try to go into greater detail, but below I’ve pasted a short simple post I use on the internet from time to time:
The reason SDA are wrong is that they teach a false gospel. See Gal 1:8, SDA teach if you fail to keep the sabbath after probation you’re damned and have the mark of the beast.
The bible says we are not saved by works of the law (Rom 3:20). Jesus died carrying our sins to the grave and rose on the third day. Conquering sin and death.
Repent and be baptized for the forgiveness of your sins and place your trust in Christ and Christ alone.
The Sabbath will not give you salvation.
The Sabbath will not give you extra assurance for the end times.
The Sabbath is no different than circumcision. The Bible says the Sabbath is obsolete.
(Col 2:16)(Heb 9:1, 4)(Heb 8:7, 13)(Gal 3:10)(Eph 2:8-10)(1 Cor 15:1-6)(2 Cor 3:4-15)(2 Cor 5:21)
Please leave a comment and tell me what you think. If you wish to use this then go for it, the more the merrier. If you have advice or a better blurb you wish to share, by all means please do so.
Armchair Theologian 
You say “repent of your sins”, but the Sabbath command is still in force…it’s still called the “sabbath” in the NT and in Luke 23:56 “they rested on the sabbath according the commandment”…Sin is the transgression of the law (1 Jn 3:4) YOU need to repent of breaking the commandment regarding the sabbath!!
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The sabbath is also called a shadow. And even obsolete. Read my other posts on leaving adventism and you will see I prove this from scripture.
http://www.armchairtheologian.info/leaving-adventism
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Hello. I really enjoy your posts. My whole family is Seventh day Adventist. My sister is a fundamentalist. Cherry picks the Bible. Doesn’t work. Lives off the state. But I am the sinner because I don’t believe in the SDA. My brother just got out of prison for pedophilia.My mom and dad bless their hearts believe whole hearted in the SDA. Is there anything that you can send me or my sister about how much information about The SDA church is false. Anything would be greatly appreciated. Thank you. Especially about the Sabbath day and Ellen G. White being a false prophet.
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I’m glad that you like them! I hope you don’t mind by I am going to paste the email that I sent to you in response to this comment below in case anybody else wants the same:
Below is a list of helpful resources for either yourself or others that you care about.
The first place I would recommend any Seventh Day Adventist starting is the New Covenant. I have a series on this which you can find here:
https://actheologian.com/leaving-adventism/the-new-covenant/
I would also recommend the series that Proclamation did, which you can find here:
http://www.lifeassuranceministries.org/studies/covenants/index.html
After that they may have questions about Ellen White, a lot of this is going to depend on how in to her they are. If they have only been exposed to the Sabbath morning quote on a powerpoint Ellen White then this will be pretty simple. But if they have read and breathed her work for many years then this will not be so easy. There will be a great deal of shame in accepting that they have been teaching their kids lies and because of that they won’t want to consider it. I would recommend a great deal of patience and love here.
You can find all my studies on Ellen White here:
https://actheologian.com/leaving-adventism/ellen-white/
If your family was hip deep into Ellen though then I recommend specifically focusing in on the Shut Door issue. This is what helps the old timers. You’re really going to have to dig into the ins and outs of it. But you can get the basics in my blog post and then follow the sources I linked to dig in and find more information. This issue is the one that helped my parents.
https://actheologian.com/2016/02/21/the-shut-door/
I would really focus on those two things first. After the New Covenant has sunk in and they are realizing Ellen White was a false prophet they should then be ready to really hear the Gospel. They will need to know that Jesus saves them even in the end times no matter what. By faith alone. A post I have that might help you with that is this one:
https://actheologian.com/2015/10/31/the-false-gospel-of-sda/
At this point I would say give them some space, and when they are ready they will probably need to look into the investigative judgment and the great controversy. I have two series dedicated to those topics which you can find below.
https://actheologian.com/leaving-adventism/investigative-judgment/
https://actheologian.com/leaving-adventism/the-great-controversy/
I wouldn’t press at all on the end times, hell, the state of the dead or other SDA particulars. They will need to realize that you’re not trying to sell a denomination to them and that there is some freedom in such issues. When they are ready to question those and learn more they should be able to do the work on their own at that point.
Every person is different though and they might need more than what I have linked above. So below are more links that I have found helpful for further analysis.
http://www.formeradventist.com/
http://lifeassuranceministries.org/proclamationmag.html
http://www.exadventist.com/
This next one is an interactive FAQ that I found helpful
http://www.exadventist.com/sdafaq/afmmain.aspx?topicid=&faqid=&question=
http://www.exadventist.com/Portals/0/Repository/Dialogue%20With%20A%20Seventh-Day%20Adventist%20by%20Samuel%20Fisk.pdf
Click to access Discovering%20the%20New%20Covenant%20-%20Greg%20Taylor.pdf
http://www.amazon.com/Neither-Catholics-Seventh-Day-Adventism-Subject-ebook/dp/B00578Y6U0
http://www.exadventist.com/book/
http://www.truthorfables.com/
http://www.biblestudiesforadventists.com/
This last one costs money, but it’s only five bucks. If you can afford it I highly recommend.
http://bookstore.ctsfw.edu/evaluaton-claims-charismatic-gifts
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What do you tell the sdas who say “oh yes, of course, we are saved by Grace but we show evidence we are saved by obedience and that includes keeping the Sabbath. They are trying their best to deny they keep the Sabbath because it is required (and we all know it is a absolute requirement for sdas) so they are saying they only keep it out of love.
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First off evidence of sanctification (good works) is subjective not objective. So you can’t say no Christians ever lie for example. Same would be true even if the Sabbath was still law.
Second, if they are saying we are saved by grace then they must also believe Ellen White is a false prophet. Because she taught that you must be perfect without a mediator at the close of probation to be saved.
In all honesty though, if they have faith in Christ for their salvation and not the Sabbath then that’s what’s most important.
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