I have shared the gospel online, in person, in newspapers...you name it...and I never once required a "secret message" or Bible code while doing so.
"The sword of the Spirit, which is the word of God" (Ephesians 6:17) is perfectly capable of doing what it was designed by God to do without any sort of "secret message" or Bible code to back it up.
If spoken in truth, God's word will cut people to their hearts.
Some will repent, and others will get angry.
This is what the Bible teaches, and this is what I have personally witnessed and experienced multitudes of times while witnessing to Muslims, Jehovah's Witnesses, atheists, agnostics, etc., etc.
Act 2:37
Now
when they heard this, they were pricked in their heart, and said unto Peter and to the rest of the apostles, Men
and brethren, what shall we do?
Act 5:33
When they heard that, they were cut to the heart, and took counsel to slay them.
Act 7:54
When they heard these things, they were cut to the heart, and they gnashed on him with
their teeth.
Neither Jesus, nor the prophets, nor the apostles, nor any disciple of Jesus Christ ever required a "secret message" or Bible code to convince their hearers, so just give it a rest lest you fulfill this "secret message":
2 Peter 2:16
"But was rebuked for his iniquity:
the dumb ass speaking with man's voice forbad the madness of the prophet. "