However, it was generally against GOD's will/law for a Hebrew man to marry (have sex with) a gentile woman, yet the bible says that it was GOD's will for Samson to be with the Palestinian. Judges 14:4. Since it was GOD's will, it was NOT against GOD's law for Samson. Samson was following GOD's will for him. It was NOT a sin for Samson.
Also, normally it is forbidden/sin to marry an adulteress. Yet, that's exactly what GOD/JESUS told Hosea to do! (Hosea 1:2) Hosea obeyed GOD. It was NOT a sin for him!
Also, normally, it would be sin to kill babies. Yet GOD commanded several times for Israel to kill everyone in a tribe/nation/city, including women and children and babies. While most people would not be able to understand the love of GOD in those events, the fact is that those children would had been sacrificed to demons by their own parents, or else raised in a demonic sadist religion to eventually murder many Israelites. It was an act of love and mercy to destroy those people and put a stop to their suffering under Satan's control.
GOD knows what He is doing! He calls different people for different tasks. GOD can, and has, commanded/led people to do what is normally not allowed. It's never sin to obey GOD. His actual living voice/will/command to you personally overrides what was written to the general population thousands of years ago!
No, GOD would never command or cause or tempt anyone to sin. BUT if HE commands something, or if it's His Will for you to do something, it's NOT sin!