Josemaria Escriva. Founder of Opus Dei
 

We are God’s children

Rest in divine filiation. God is a Father — your Father! — full of warmth and infinite love.
—Call him Father frequently and tell him, when you are alone, that you love him, that you love him very much!, and that you feel proud and strong because you are his son.
The Forge, 331

Children... How they seek to behave worthily in the presence of their parents.
And the children of kings, in the presence of their father the king, how they seek to uphold the royal dignity!
And you? — Don't you realize that you are always in the presence of the great King, God, your Father?
The Way, 265

There is only one race in the world: the race of the children of God. We should all speak the same language, taught us by our Father in heaven — the language Jesus spoke with his Father. It is the language of heart and mind, which you are using now, in your prayer — the language of contemplation, used by men who are spiritual, because they realize they are children of God. This language is expressed in a thousand motions of our will, in the clear insights of our minds, in the affections of our heart, in our commitment to lead a virtuous life, in goodness, happiness and peace.
Christ is passing by, 13

'Father', said that big fellow, a good student at the university (I wonder what has become of him), 'I was thinking of what you told me — that I'm a son of God! — and I found myself walking along the street, head up, chin out, and a proud feeling inside... a son of God!'
With sure conscience I advised him to encourage that 'pride.'
The Way, 274

Our Lord has come to bring peace, good news and life to all men. Not only to the rich, nor only to the poor. Not only to the wise nor only to the simple. To everyone, to the brothers, for brothers we are, children of the same Father, God. So there is only one race, the race of the children of God. There is only one colour, the colour of the children of God. And there is only one language, the language which speaks to the heart and to the mind, without the noise of words, making us know God and love one another.
Christ is passing by, 106


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