Dear Diego:

I am always amazed at the ignorance of some priests. Much of their errors are born from well-meaning sentiments, but nonetheless they teach error. It is largely from lack of thinking and intellectual sloppiness that well-meaning priests assert ideas that, perhaps unbeknownst to them, are heretical or otherwise in violation of Church teaching.

Some of this sloppy thinking and ignorance came from the seminaries. From the 1970s to the 1990s many seminaries were notorious for their lack of fidelity to the Church and for their not training potential priests how to think with reason and intellect. This is even more surprising since philosophy is a requirement in academic training of a priest.

Anyway, perhaps this priest you heard falls somewhere in this description. From your description the priest sounds well-meaning in trying, perhaps, to make us feel closer to Jesus. Whatever his thinking, it is wrong. Not only is it wrong, but it might be heretical.

Jesus is fully God and fully man. This is the infallible teaching of the Church. This priest seems to have forgotten that. If God the Father, the 1st Person of the Trinity, is perfect, so is Jesus, who is God the Son, the 2nd Person of the Trinity. God cannot be imperfect.

The point of Matthew 5:48, which is a summary of the entire chapter, is that we are called to perfection. While we cannot be as perfect as God, our Lord and our God is a model to which we aspire. Because Jesus referenced the Father does not imply that he was imperfect in the quest for perfection. Luke 6:36 says, "Be merciful, even as your Father is merciful." Does this priest also think that Jesus was imperfect in mercy? 1 Peter 1:15-16 says, "...but as he who called you is holy, be holy yourselves in all your conduct; since it is written, 'You shall be holy, for I am holy.'" Does this priest suggest that Jesus is imperfect in holiness?

Jesus was being perfected only in the Greek sense of the word  telios, which is often translated into English as "perfect". Telios refers to something being completed, fulfilling its full purpose.

We see this idea of being perfected, that is of telios, applied to Jesus in Hebrews in chapter 5 verses 8-9:

"Although he was a Son, he learned obedience through what he suffered; and being made perfect he became the source of eternal salvation to all who obey him."

Since Jesus was sinless, and was God, how does he need to be perfected? Again, this is referring to the Greek notion of telios, to come to completion, fulfilling a purpose. Jesus fulfilled His purpose by His death and Resurrection. By His suffering he became the propitiation for our sins. He died for us to redeem mankind from the death and the slavery of the devil. This was the completion of His love to which he came to earth to give us.

The priest is also incorrect about temptation. The Navarre Bible Commentary explains (bold is my emphasis):

Jesus, our Saviour, allowed himself to be tempted because he so chose; and he did so out of love for us and to instruct us. However, since he was perfect he could only be tempted externally. Catholic teaching tells us that there are three levels of temptation:

1) suggestions, that is external temptation, which we can undergo without committing sin;

2) temptation, in which we take a certain delight, whether prolonged or not, even though we do not give clear consent; this level of temptation has now become internal and there is some sinfulness in it;

3) temptation to which we consent; this is always sinful, and, since it affects the deepest part of our soul, it is definitely internal.

By allowing himself to be tempted [externally], Jesus wanted to teach us how to fight and conquer our temptations. We will do this by having trust in God and prayer, with the help of God's grace and by having fortitude.

There was no imperfection in Jesus by his allowing himself to be tempted. There is no imperfection in us if the temptation are merely suggestions presented to us. I can be tempted to get drunk, that is, a friend may suggest to me that we ought to go out and get drunk. This is merely a suggestion made to me that I readily decline. There is no delight in it (def 2 above), and no consent (def 3 above).

So, what else does this priest suggest that Jesus did in the "doing" that was imperfect?

Well, the correct answer to that is nothing. Jesus did nothing in the "doing" that was imperfect. Nothing. Nada. All actions of Jesus were in perfection, including the temptation and including the righteous anger with the money changers at the Temple.

Bottomline: This priest is wrong and should think more clearly with the teachings of the Church and with moral theology, and then correct himself from the pulpit. 

As to the reference to the Father: Jesus refers to His Father in these passages about perfection, mercy, and holiness, because he is speaking to God's children (us) to seek the perfection of the Father. Heydock Bible commentary explains:

Seeing then that we are thus blessed as to be called, and to be the children of so excellent a Father, we should endeavour, like Him, to excel in goodness, meekness, and charity; but above all in humility, which will secure to us the merit of good works, through the infinite merits of our divine Redeemer, Master, and model, Christ Jesus the Lord.

I hope this helps.

God Bless,
Bro. Ignatius Mary