This is true inasmuch as that even a child is saved as he/she trusts and grows in Him.
What you said is false inasmuch as Christ spent Three and One half years teaching the Disciples, and 40 days after the ascension. The entirety of the Pauline letters are devoted to instructing what one is in fact TO DO.
Do you suppose that Christ uses human agents to teach, mentor, rebuke, and the like? And if so, are those things useless and not of import?
Of course not.
To understand why it is thaat we Orthodox confess publically our sins- in the witness of an elder (priest is an English rendering of what our elders are known as -presvyteros in Greek, elder hand selected by the episkopos, as is the biblical and Apostolic teaching)- one must read the whole of the scriptures, not just the touchy-feely scriptures that assure us when our hearts condemn us. David confessed to Nathan, then David composed a song (psalm) which indicates the response and action of the penient:
- Turn Your Face from my iniquities
- Wash my from my iniquity
- Sprinkle me with hyssop
- The bones that were afflicted shall rejoice
- I will teach your ways to the sinners
- In your Kindness O Lord, be bountiful to Zion
- and may the Walls of Jerusalem be restored
"Old Testament" you may say. Fine- do a comparative study in the NT, and see the parallels.
- Confess your sins to one another, and be healed
- Wash your hands you sinners
- Draw near to God, and He will draw near to you
Repentance is a process, one which does not abrogate nor deny His Once and for All sacrifice. No, rather, it draws upon it, a Sacrifice that need not be repeated.
Faith is not passive.
Trusting in Him is a very active thing. Ask the martyrs.
They were shipwrecked, beaten, hungered...they prayed without ceasing, fasting for the salvation of themselves and others.
Try it...it works.
It changed and changes the world.