Q 122. What does the first petition mean?
A. “Hallowed be your name” means:
Help us to truly know you,1
to honor, glorify, and praise you
for all your works
and for all that shines forth from them:
your almighty power, wisdom, kindness,
justice, mercy, and truth.2
And it means,
Help us to direct all our living—
what we think, say, and do—
so that your name will never be blasphemed because of us
but always honored and praised.3

1 Jer. 9:23-24; 31:33-34; Matt. 16:17; John 17:3
2 Ex. 34:5-8; Ps. 145; Jer. 32:16-20; Luke 1:46-55, 68-75; Rom. 11:33-36
3 Ps. 115:1; Matt. 5:16

Q. 122. What does the first request mean?

A. “Hallowed be your name” means,

Help us to really know you,
to bless, worship, and praise you
for all your works
and for all that shines forth from them:
your almighty power, wisdom, kindness,
justice, mercy, and truth.

And it means,

Help us to direct all our living—
what we think, say, and do—
so that your name will never be blasphemed because of us
but always honored and praised.

http://www.crcna.org/pages/heidelberg_prayer.cfm#Day 47

Q. 122. Which is the first petition?

A. “Hallowed be thy name”; that is, grant us, first, rightly to know thee, and to sanctify, glorify and praise thee, in all thy works, in which thy power, wisdom, goodness, justice, mercy and truth, are clearly displayed; and further also, that we may so order and direct
our whole lives, our thoughts, words and actions, that thy name may never be blasphemed, but rather honoured and praised on our account.

http://www.ccel.org/creeds/heidelberg-cat-ext.txt