Dan M. Ross told NBC 2 he was guided by his faith when he tried to send yellow roses to the accused shooter, who has been charged with 13 premeditated killings in the Nov. 5 attack on soldiers waiting to deploy from Fort Hood.
Twenty-nine others were wounded, including Hassan, who, doctors say, may be permanently paralyzed.
Ross ordered flowers and requested a card that read "In God's eye, and those who submit, you are a hero!" But instead of completing the $59.95 order, the owner of the Texas flower shop said he reported it to the Army base and the FBI.
Ross, a Vietnam vet, said he has kids in the military, but he wanted to reach out as a show of respect.
With a Bible close by, a declaration of his Christian beliefs and a website outlining his visits by an angel, Ross said in a television interview that he believes we should all love our enemies.
Ross said he's hopeful some kind of good can come out of the shooting at Fort Hood and hopes the incident will bring an end to the conflict between religions.
The local sheriff's office did confirm the FBI visit to Ross' home, but agents for the FBI will not comment on the visit or the investigation.
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Forensic Psychiatrist on Possible Mindset of Ft. Hood Suspect
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Soldier Opens Fire at Ft. Hood; 13 Dead
U.S. Army Base Violence Has Bloody History
Obama: Fort Hood Shooting "Horrific"
Fast Facts: Fort Hood
Tragedy at Fort Hood