I found a very clear statement in Doctrine and Covenants 20.  Joseph Smith cuts through centuries of confusion.

That as many as would believe and be baptized in his holy name, and endure in faith to the end, should be saved—

. . . .

29 And we know that all men must repent and believe on the name of Jesus Christ, and worship the Father in his name, and endure in faith on his name to the end, or they cannot be saved in the kingdom of God.

30 And we know that justification through the grace of our Lord and Savior Jesus Christ is just and true;

31 And we know also, that sanctification through the grace of our Lord and Savior Jesus Christ is just and true, to all those who love and serve God with all their mights, minds, and strength.

32 But there is a possibility that man may fall from grace and depart from the living God;

33 Therefore let the church take heed and pray always, lest they fall into temptation;

34 Yea, and even let those who are sanctified take heed also.

God is a loving Father.  You are His child.

From which it follows that

He will allow you to repent (because He is loving);

that you need to repent, i.e., change (because you need to grow up to become like your Father);

that He will give you whatever help He can without you earning it, i.e., grace (because He is a loving Father)–you aren’t capable of earning it (you are a still a child, if you could merit grace you would not need grace);

that you can refuse His help and turn away from growing up (because you are His child, which means you have agency like He does, and He loves you, which means He will not force you ), which is the same as saying that your continued growth needs your continued effort and cooperation;

Neither His help nor your efforts to accept and process His help will happen all at once (because you are a child, the distance between you and adulthood is very great and cannot be bridged all at once if you are still to remain the you that He loves).