I know these 'resolutions' weren't made on New Years Day, but they are 'resolutions' still:
Act_18:6 And when they opposed themselves, and blasphemed, he shook his raiment, and said unto them, Your blood be upon your own heads; I am clean: from henceforth I will go unto the Gentiles.
Rom_15:18 For I will not dare to speak of any of those things which Christ hath not wrought by me, to make the Gentiles obedient, by word and deed,
Rom_15:24 Whensoever I take my journey into Spain, I will come to you: for I trust to see you in my journey, and to be brought on my way thitherward by you, if first I be somewhat filled with your company.
Rom_15:28 When therefore I have performed this, and have sealed to them this fruit, I will come by you into Spain.
1Co_16:5 Now I will come unto you, when I shall pass through Macedonia: for I do pass through Macedonia.
1Co_16:6 And it may be that I will abide, yea, and winter with you, that ye may bring me on my journey whithersoever I go.
2Co_11:12 But what I do, that I will do, that I may cut off occasion from them which desire occasion; that wherein they glory, they may be found even as we.
2Co_12:14 Behold, the third time I am ready to come to you; and I will not be burdensome to you: for I seek not yours, but you: for the children ought not to lay up for the parents, but the parents for the children.
2Co_13:2 I told you before, and foretell you, as if I were present, the second time; and being absent now I write to them which heretofore have sinned, and to all other, that, if I come again, I will not spare:
Phm_1:19 I Paul have written it with mine own hand, I will repay it: albeit I do not say to thee how thou owest unto me even thine own self besides.
2Pe_1:12 Wherefore I will not be negligent to put you always in remembrance of these things, though ye know them, and be established in the present truth.
2Pe_1:15 Moreover I will endeavour that ye may be able after my decease to have these things always in remembrance.
3Jn_1:10 Wherefore, if I come, I will remember his deeds which he doeth, prating against us with malicious words: and not content therewith, neither doth he himself receive the brethren, and forbiddeth them that would, and casteth them out of the church.
Yes, I know very well that the results of any intention of my will is in the Hands of the Lord and that we cannot do anything except what He foreknew...but to say 'making new year's resolutions is a "sin" sounds religious to me, and over-righteous. It could be that making resolutions is a means by which God reveals His sovereignty and tests our hearts, but to completely negate the 'making of resolutions' as a sin makes sinners of the Apostles.