''If he is bringing it as a thanksgiving offering... ''[Tzav 7:12 ]
Rashi comments on when a thanksgiving offering is brought:
To give thanks to G-d for a miracle that had happened to a person. For instance:
1. those who made a sea voyage, or
2. journeyed in the desert, or
3. those who had been in prison, or
4. a sick person who recovered.
All these are required to give thanks to G-d since regarding them, the verse states ''They will give thanks to G-d for His kindness and for His wonders to mankind, and they will slaughter sacrifices of thanksgiving.'' [Psalms 107:21-22]
Chassidic thought has a further sequence of the four cases that require a thanksgiving offering, corresponding to the process by which the soul descends into the world:
1. Sick person: When the soul leaves its source beginning its journey down into this world, the intense love for G-d which is experienced previously is weakened. So the soul becomes ''sick'' with its desire to regain its lost love.
2. Imprisonment: As the soul descends further downwards, it becomes affected by the progressive confinement of the spiritual and physical worlds, until it is eventually ''imprisoned'' in a body.
3. Sea voyage: While the soul is living in this world, there is the danger that it will ''drown'' in the turbulent waters of worldliness and physicality.
4. Desert: The soul may regress further, G-d forbid, to the point that the person lives a life devoid and barren of any spiritual meaning whatsoever.
And since these challenges are great, the soul is made to swear an oath before it leaves its source - ''be righteous and don't be wicked'' - giving it the strength to prevail against all odds.
Based on Sefer HaMaámarim 5737 Lubavitcher Rebbe