Both "The Wanderer" and "The Seafarer" contain references to Christianity. Anglo-Saxons passed on their epics and poetry through oral tradition. While originally Pagan, the Anglo-Saxons began to accept and practice Christianity and this change was reflected in the first written texts.
As for the Christian attitudes found in the elegies/laments, both illustrate the problems one faces when God is ignored. Both speakers tell readers of lives that have passed on--deaths of friends, family, and kings. Now, alone, each poetic persona sails along continuing to do what they know how to do.
In the end, both speakers give readers their final words of wisdom. Each proceeds to tell readers about the importance of God and of belief in him. In "The Wanderer," the speaker mentions how everything is gone--horses, money, friends, kinsmen. The only thing which the speaker can cling to is faith. It is in this faith that one can find "mercy / consolation from the Father in heavens, / where, for us, all permanence rests."
The speaker in "The Seafarer" also recognizes the importance of faith. For this speaker though, righteous fear is of the utmost importance. One must fear the Lord in order to come to heaven: "Blessed is him who lives humbly / --to him comes forgiveness from heaven." Again, as with "The Wanderer," the speaker is educating the reader on the importance of faith and a relationship with God.
Regardless of which poem one looks at, each illustrates a Christian attitude. Both explain the importance of faith in God and the knowledge that God is all one will have after death.