Dhammapada 1 & 2.

The mind precedes words & deeds, it directs and it creates:
if one speaks or acts with an impure mind,
unhappiness therefore will follow [him/her]
like the wheel the beast of burden's foot.

1. Manopubbaṅgamā dhammā manoseṭṭhā manomayā:
manasā ce paduṭṭhena bhāsati vā karoti vā,
tato'naṃ dukkham-anveti
cakkaṃ'va vahato padaṃ.

The mind precedes words & deeds, it directs and it creates:
if one speaks or acts with a pure mind,
happiness therefore will follow [him/her]
like an indiscessible shadow.

2. Manopubbaṅgamā dhammā manoseṭṭhā manomayā:
manasā ce pasannena bhāsati vā karoti vā,
tato'naṃ sukham-anveti
chāyā'va anapāyinī.

Translation from the Pāḷi: 白狐

-- NOTES --

dhamma = conduct [word & deed]; norm; truth.
dukkhaṃ + anveti = unhappiness, dissatisfaction + follows/will-follow.
sukhaṃ + anveti = happiness, comfort + follows/will-follow.
tato'naṃ = tatonidānaṃ = on account of that
OR > naṃ = taṃ = him/her

-- SOURCES --

http://www.accesstoinsight.org/tipitaka/
http://www.budsas.org/ebud/dict-ep/
http://www.buddha-vacana.org/toolbox/dico.html
http://www.buddhanet.net/pdf_file/paligram.pdf