Teach them to observe all things Christ commanded

Just before Jesus left the Earth, He gave one final command: "All authority has been given to Me in heaven and on earth. Go therefore and make disciples of all the nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, teaching them to observe all things that I have commanded you; and lo, I am with you always, even to the end of the age."

This command, known as the "Great Commission", is often only remembered in part. Every Christian remembers "go now, and make disciples of all nations", and most remember "baptising them in the name of the Father, and of the Son and of the Holy Spirit", but not many remember "teaching them to observe all things that I have commanded you".

Because of this, many Christians like to pick and choose when to be consistent. "It's not a Gospel issue" is a common saying, usually used to defend some obviously false doctrine. But nowhere in the Bible can such a distinction be found. Jesus was rather clear: Teach them to observe all things that I have commanded you. Not once, when debating doctrine, can anyone in the Bible be found saying "it's not a Gospel issue".

It's not in red letters. It's not in black letters. The fact is, every red letter confirms every black letter, which means Christ Himself insists that the scriptures be observed; not a jot or tittle is irrelevant. If you're going to claim to be Christian, you're going to treat every word in the Bible as very important (and yes, that does include those boring genealogies no one enjoys reading). "It's not a Gospel issue" is not an excuse for ignoring an issue, and it's certainly not an excuse for coming down on the wrong side of an issue.