Here there are three guidelines to purify our hearts.
**First: **in your prayer ask God to help you to have a pure heart.
Second: He will grant you a conscience to tell you when you are sinning in your heart.
Take notice of it; change what you have done wrong, ask God to forgive you and do not do it again. And if you fall again, again ask God to forgive you, but always with the intention of correcting yourself, until you manage, with His grace, to stop sinning in your heart.
Third: Do not have scrupulous with minute things, go for the bad ones, and then the rest.
(cf.1 John 3:17-24)
Do not bother if you are sinning because you drank too much coffee and you should restrain your desires which are not a needed to keep your health. You will do this afterwards. Make sure that you do not desire the girlfriend of you friend, the wife of your neighbor, a colleague at your job. Make sure these big things to go first from your heart. (cf. Mt 5:27-28),
**Do not get angry without reason **(Mt 5:22 NKJV; Saint Agustin - The teaching of the Lord at the Mountain - First Book 9.21) -the only reason being when we are faced with immorality (cf. Hb 12:4) – We must not tolerate the ones who teach immorality (cf Ap 20:2)
And never hate anyone: **NEVER **"Any one who hates his brother is a murderer" 1 Jn 3:15
If any one says, “I love God", and hates his brother, he is a liar" 1Jn 4:20) and always forgive when you are asked for. (cf. Lk 17:4) If you are more perfect, even you will forgive without been asked for it.
When you are attack for being moral or for a false accusation, do not respond with bad words or actions. Just make your point straight without anger. (cf. Lk 6:22; cf. 1 Pet 2:19; 3:14)
Do not lie, this is very important and you have to understand it very well:
there is not one lie that can come from God.
NEVER SAY ANY LIE OF WHAT SO EVER TYPE, they make us unclean.
"…know that no lie is of the truth."1 Jn 2:21
When the devil “lies, he speaks according to his own nature, for he is a liar and the father of lies”. Jn 8:44 And the fate of the liars at the end times, is in the lake of fire. Rev 21:8
Carry on in the same way, listening to your conscience to purify your heart, your thoughts.
May God give us the love to keep His commandments, to start with the purification of our heart and be able to trust and believe all what Jesus taught us.
If we do not hate evil, our love will never be genuine. (cf. Rom 12:9)
"If you know that he is righteous, you may be sure that every one who does right is born of him." 1 Jn 2:29
"… let no one deceive you. He who does right is righteous, as he is righteous. 8 He who commits sin is of the devil; for the devil has sinned from the beginning." 1 Jn 3:7-8
In the love of Christ,