Recently, I had a few discussions with different people where they suggested various ideas boiling down to "I'm not sinless yet, I just need to pray harder and God will make me holy."
It's a real shame this idea is so well entrenched. You won't find it anywhere in scripture. Every person you ever meet who has repented of their sins (that is, does not do anything that deviates from their belief of what God would do in there place) will tell you emphatically it is a lie. But instead of believing people who have actually done a thing, people prefer to entertain what they wish were true.
One person was telling me how if we pray fervently, God will fill us with his love, and then we will want to actually obey him. He was referring to this passage:
Wherefore, my beloved brethren, pray unto the Father with all the energy of heart, that ye may be filled with this love, which he hath bestowed upon all who are true followers of his Son, Jesus Christ; that ye may become the sons of God; that when he shall appear we shall be like him, for we shall see him as he is; that we may have this hope; that we may be purified even as he is pure. Amen. (Moroni 7:48)
Here are the problems with that interpretation:
1) It contradicts very plain statements by the same author.
In this same chapter, in fact, the author states that Jesus gives us power to do everything according to his will, and follows that immediately with the Lord's command to repent:
33 And Christ hath said: If ye will have faith in me ye shall have power to do whatsoever thing is expedient in me.
34 And he hath said: Repent all ye ends of the earth, and come unto me, and be baptized in my name, and have faith in me, that ye may be saved. (Moroni 7)
There are plenty more of these.
2) The provided condition of the promise to be filled with the love of God is to be a "true follower of...Jesus Christ...." You are not a true follower of Jesus Christ unless you...you know, truly follow him.
3) The modern interpretation of what it means to "pray unto the Father" is not what it once was. We read this and think "prayer is closing my eyes and asking God for things." The ancients understood that prayer meant the intentional subversion of one's own will to the will of the Father. For example, consider what Jesus was doing in the garden of Gethsamane. He did not say, "Father, I'm about to do whatever I feel like, and I sure hope you give me what I want." Instead he found out what the Father wanted him to do, and bent his will to the will of the Father.
Here is some evidence for my claim.
But behold, I say unto you that ye must pray always, and not faint; that ye must not perform any thing unto the Lord save in the first place ye shall pray unto the Father in the name of Christ, that he will consecrate thy performance unto thee, that thy performance may be for the welfare of thy soul. (2 Nephi 32:9)
Does this verse instruct us to as God to magically convert whatever we were going to do anyway into something he blesses us for, or does it mean to actively seek and submit to what God would do in our place?
And again I say unto you as I have said before, that as ye have come to the knowledge of the glory of God, or if ye have known of his goodness and have tasted of his love, and have received a remission of your sins, which causeth such exceedingly great joy in your souls, even so I would that ye should remember, and always retain in remembrance, the greatness of God, and your own nothingness, and his goodness and long-suffering towards you, unworthy creatures, and humble yourselves even in the depths of humility, calling on the name of the Lord daily, and standing steadfastly in the faith of that which is to come, which was spoken by the mouth of the angel. (Mosiah 4:11)
Do you think that this call to humility and consideration of one's nothingness before God is about asking him to honor and magnify whatever we feel like doing?
And at some period of time they will be brought to believe in his word, and to know of the incorrectness of the traditions of their fathers; and many of them will be saved, for the Lord will be merciful unto all who call on his name. (Alma 9:17)
Do you think these people were being commended for continuing to follow the incorrect traditions of their fathers after they were shown the incorrectness of those traditions?
Here's the truth:
Fulfilling the commandments comes before a remission of sins, which comes before meekness and lowliness of heart, which comes before the visitation of the Holy Ghost, which comes before being filled with perfect love:
25 And the first fruits of repentance is baptism; and baptism cometh by faith unto the fulfilling the commandments; and the fulfilling the commandments bringeth remission of sins;
26 And the remission of sins bringeth meekness, and lowliness of heart; and because of meekness and lowliness of heart cometh the visitation of the Holy Ghost, which Comforter filleth with hope and perfect love, which love endureth by diligence unto prayer, until the end shall come, when all the saints shall dwell with God. (Moroni 8)
The solution for your failure to repent is not to pray harder. It is to be more honest about how good God is. It is to come to terms with the fact that you don't actually love him, even though he loves you. It is to reconcile to his goodness through bending your will to his, because you are ready to start believing he is everything he purports to be.