If I still had a son, sitting here,
As brave as Baldur was,
You would not escape unscathed from the hall,
Before you fought with him.
- Frigg (Freyja) to Loki in the Eddic poem Lokasenna
In the Eddic poems, only three gods are unequivocally claimed to be the sons of Odin. These three gods are Thor, Baldur, and Vali.
The Poetic Edda is a collection of poems gathered from wandering minstrels as early as ca. 985. Scholars have debated and speculated over time with hypothetical thoughts of who the actual authors were of the various poems -- yet no conclusions have ever been reached. However, the references to who the gods are and how they are related is accepted as evidence of individuals and their roles in mythology.
Thor, Baldur, and Vali are also mentioned as the sons of Odin in the skaldic poems (a group of poets associated with the Scandinavian and Icelandic courts of the Viking age leaders, now characterised as Old Norse poetry); the Gesta Danorum, the great literary works of medieval Denmark; and in the Gylfaginning section of Snorri Sturluson's Prose Edda written in the year 1220.
Thor is a mighty god who wields a mountain-crushing hammer, Mjollnir, in battle. He is fierce-eyed, red-haired and red-bearded. He is associated with thunder, lightning, storms, oak trees, strength, destruction, fertility, healing, and the protection of mankind. Thor is a much loved god of the Viking Age. Emblems of his hammer were worn in defiance during the Christianization of Scandinavia. In the same period, Norse pagans had personal names which contained "Thor" to bear witness of their loyalty to him.
Thor rides in his chariot led by two goats, Tanngrisnir and Tanngnjiuastr which he resurrects after eating them. He wears the belt, Megingjiuariua, and the iron gloves, Jiuarngreipr, and owns the staff called Griuaiuarviualr.
In the poem Volupsa, Odin disguises himself and goes to a volva (seeress) to know the future events. The seeress tells of the history of the universe and reveals the future to Odin. She foretells of the death of Thor as he does battle with the great serpent during the war at Ragnariuak, and there he will slay the monstrous snake, yet dies when walking away from the dead serpent:
Hither there comes the son of Hlothyn,
The bright snake gapes to heaven above.
Against the serpent goes Othin's son.
In anger smites the warder of earth.
Forth from their homes must all men flee.
Nine paces fares the son of Fjorgyn,
And, slain by the serpent, fearless he sinks
- Translation by Henry Adams Bellows, 1810 - 1900
Thor's brother, Baldur, is a more gentle god. He is associated with light, beauty, love, and happiness. What Thor accomplishes with might, Baldur accomplishes with love and gentleness. Baldur has the mightiest ship ever built and his hall surpasses all others in beauty.
In Gylfaginning, Baldur is described as follows:
The second son of Odin is Baldur, and good things are to be said of him. He is best, and all praise him; he is so fair of feature, and so bright, that light shines from him. A certain herb is so white that it is likened to Baldr's brow; of all grasses it is whitest, and by it thou mayest judge his fairness, both in hair and in body. He is the wisest of the iuasir, and the fairest-spoken and most gracious; and that quality attends him, that none may gainsay his judgments. He dwells in the place called Breidablik, which is in heaven; in that place may nothing unclean be. Brodeur's translation
Baldur and his mother, Freyja, both had the same prophetic dream of his death. Freyja so loved her second son that she made every object on earth vow to never harm Baldur. She did not include mistletoe in this promise, for she thought mistletoe too insignificant and young to bother with. When the shape shifter, Loki, heard of this he made an arrow from mistletoe. This arrow he gave to Hoor, one of Baldur's half brothers. Hoor was blind and knew not what he held. During a game when others were hurling objects at Baldur to watch them bounce off the protected god, Hoor hurtled the arrow. The mistletoe arrow struck and killed Baldur.
Vali is a half brother of Thor and Baldur. He is the son of Odin and the goddess Rindr. Odin seduced Rindr and from this was born Vali, for the sole purpose of avenging Baldur's death. Vali grew to a man within one day of his birth and slew Hoor.
The tragedy of the death of Baldur is the first in a series of events that lead to the destruction of the gods at Ragnarok, the "final destiny of the gods".
Thor's Battle Against the Ettins (1872) by Marten Eskil Winge
Wikipedia Public Domain
Baldur the Good by Jacques Reich (1852 - 1923)
Wikipedia Public Domain