Psalm 119:57-64  " The Lord is my portion;"   Matthew Henry's commentary says that this means that the psalmist makes God's favor the source of life, happiness, and satisfaction.  "Others place their happiness in the wealth and honors of this world.  Their portion is in this world. Their portion is in this life; they look no further; they desire no more;..."  Like Lazarus and the rich man that Jesus talked about in Luke 16,  the rich man had his portion  ( he was satisfied and happy with his riches) while living, but Lazarus receives his in the bosom of Abraham, after he died.
According to the dictionary a portion refers to the part of something allotted to you.  Your part of an inheritance, your part of a meal.  When Israel finally entered the promised land each tribe was assigned a portion, a part of the land. But the tribe of Levi was not given land, their "portion" was The Lord.  Having The Lord as your allotment, your portion, means He is ALL you rely on and live by.  To say that The Lord is your portion, your only source of life, your only desire, then it follows that you will do everything you can to honor Him, serve Him, and please Him.  The psalmist says that he has:
Promised to keep God's words. ( Commitment)
Prayed for God's favor. (Humility)
Considered his own ways. (Confession )
Turned his feet to obey.  (Repentance)
Didn't delay or hesitate . ( Obedience)
Not forgotten the Word even in times of great distress. (Endurance)
Gotten up in the middle of the night just to thank The Lord. (Gratitude)
Became a friend to all who fear The Lord. (Fellowship)

In other words, he has committed himself completely to the One who is his All in all.  Why?  Because of Who God is, "The earth is full of Thy lovingkindness, O Lord".  The God Who is infinite, eternal, almighty, all-powerful, and all-knowing, fills the earth with His own love and mercy.  He is all we need. He is the desire of our hearts. Nothing and no one else can satisfy.  There is no other true source of happiness. Everything else fails.  God alone is worthy of our devotion.  Oh Lord, I also entreat Thy favor with all my heart. Teach me Your ways.  You are my portion. Amen.

I Peter 1:1-5
Peter addresses this letter to the "chosen"ones.   Chosen according to God's eternal knowledge, sanctified (set apart) by the Holy Spirit, for obedience to Jesus Christ, being covered by His blood.  It is by God's mercy that we are "born again".  It is through the resurrection of Jesus Christ that we are given a "living hope".  Hope for eternity, "an inheritance which is imperishable and undefiled and will not fade away, reserved in heaven for you." The Lord is my portion.
This promised inheritance is given to us.  We are "protected by the power of God through faith for a salvation ready to be revealed in the last time." v5

Praise and honor and blessing to our God Who has given us such grace and showed us such mercy.  Thank You Lord for salvation that is not just for past sins, but for eternal glory. We have a LIVING HOPE through Jesus Christ our Lord. A portion much more valuable than any earthly treasure.  Oh Lord may I walk in Your ways and live in the light of Your Word.  Be Thou my portion always. Amen.