My little children, let us not love in word, neither in tongue; but in deed and in truth. And hereby we know that we are of the truth, and shall assure our hearts before him. For if our heart condemn us, God is greater than our heart, and knoweth all things. Beloved, if our heart condemn us not, then have we confidence toward God. And whatsoever we ask, we receive of him, because we keep his commandments, and do those things that are pleasing in his sight.
1 John 3:18-22
I’m not sure about anyone else, but as for me, I know there have been times in my life when I’ve wanted to ask a blessing from Heavenly Father or I wanted to seek his counsel in prayer, but I did not because I felt that I wouldn’t receive it because I wasn’t worthy. When I found this scripture and read it, I learned something very important. I learned that if I wanted to be able to call upon the powers of heaven, then I must always strive to keep the commandments. I know that this sounds so simple, but for some reason, this scripture has always helped me to remember that. I know now that when I go to God to seek his blessings, I can ask in confidence because I keep his commandments.
see also D&C 121:45