πατήρ (patēr)

The Greek word, πατήρ (patēr) - according to the lexicon, this word can mean:

"generator or male ancestor -
-either the nearest ancestor: father of the corporeal nature, natural fathers, both parents
-a more remote ancestor, the founder of a family or tribe, progenitor of a people, forefather
-fathers i.e. ancestors, forefathers, founders of a nation
-one advanced in years, a senior"

When used in relation to the physical families of this physical world, "father" would be appropriate. When used of a country or tribe, the word would refer to ancestors, forefathers, founders, etc.

In ancient times this term also applied to one who was ones superior - to be translated to "master" or "lord."

Yet these are all references to relationships within the physical world - namely those relating to a physical nation or a physical family, or ones position in society. When used in reference to God, the term takes on another meaning and thus a deferential translation.

Because God is above the realm of the physical - as indicated by Jesus - that He is beyond the physical and of the spirit - the spiritual realm. Therefore, to translate this word to the lowest common denominator - i.e., "father" which refers to a physical family - would not be appropriate with reference to the Supreme Being.

Given the definition above and the recognition of God's superior spiritual position, the more appropriate translation of this Greek word when referring to God would be "Creator" because this indicates God's ability as "Generator" as noted above - being the ultimate Source of not only Jesus, but all things and all beings.

In addition, the word πατήρ (patēr) was also utilized as Jesus in a more intimate basis, as "my" (ἐγώ egō) πατήρ (patēr). This has often been translated to "my Father." However, again since Jesus is not discussing such a relationship akin to the physical body - where fatherhood prevails, the more appropriate syntax would relate to the spiritual relationship between Jesus and the Supreme Being - being one of loving servant and his LORD, or Master. Thus a more appropriate translation would be akin to "my LORD" in most cases, as this better captures both the devotional intimacy as well as the loving servitude relationship between Jesus and the Supreme Being.

Further basis for this is that the Greek word πατήρ (patēr) was frequently used in ancient times to indicate a relationship of one's superior - as historically a senior person was addressed frequently with this word - even when there was no familial relationship. Thus "my lord" was the typical usage that carried this forth into the English language in such greetings to superiors in ancient times.

This translation would also correspond to the use of יְהֹוָה (Yĕhovah) through the Old Testament - often translated to "Lord" throughout the Old Testament. Yet certainly, Yĕhovah or Jehovah - which refers to the Original Person and Source (or Creator/Father) of everything - is being stated in the original Hebrew.

For this reason, references to God using πατήρ (patēr) include the capitalization system employed by early English translators - to LORD.

There is, in fact, a basis to believe that Jesus was actually originally speaking the name "Jehovah" in his Aramaic tongue - which was later transcribed into Greek as πατήρ (patēr), relating to the basis that Jehovah was considered the 'God of gods' (often translated to "Jehovah of the Hosts") - which was referred to in the ancient Greek vernacular, as the "Father of the gods."

But we must be reminded that Jesus does not refer to this relationship as exclusivity, as he also says "your" σύ (sy) πατήρ (patēr), as in:
"Do not be like them, for your Father [LORD] knows what you need before you ask Him." (Matt. 6:8)
"Be merciful, just as your Father [LORD] is merciful." (Luke 6:36)
In such cases - again since Jesus is not speaking of their relationships of their physical bodies - depending upon the context, the more appropriate translation would be "your LORD"  when referring to their position of devotional servitude - or "Creator" when referring to our position as being created by God.

We can see more vividly how Jesus utilized such a usage as he compared his worship of God to the Jewish officials' allegiance to the illusory nature of worldly things in this more appropriate translation:
"I speak the things I know from my LORD and you also do the things you know from your lord." (John 8:38)
In this last instance, Abraham (who the Jewish officials were referring to) was not their father. Nor was the reference Jesus was referring to in this text. "Father" thus would not be appropriate. Rather, we find in the discourse in John 8:38-44 that the exchange relates to devotional servitude rather than familial relations ("lord" below is translated to "father" among ecclesiastical translations):
They replied to him, saying, "Abraham is our lord." Jesus said to them, "If you are Abraham's servants, then you should serve Abraham." But as it is, you are seeking to kill me - a man who has spoken the Truth to you, which I have heard from God. Abraham would not do such things. You are serving your own lord." They said to him, "We do not subject to idols; we have one lord, God." Jesus said to them, "If God were your lord, you would love me, for I have come here from God. I have not come on my own; God sent me. Why is it you do not understand what I am saying? It is because you cannot hear my teachings. You follow your lord, the opposer of God, and you want to do what pleases your lord. He was a slayer from the beginning, and does not stand in the truth because there is no truth in him. Whenever he speaks falsely, he speaks from his own nature, for he is a liar and the master of lies." (John 8:39-44)
If we were to replace each occurrence of "lord" in the above exchange with "father" as is done in most ecclesiastical translations - it would simply not make any sense. This would create such misnomers as, "father of lies" (instead of the more logical translation, "lord of lies" or "master of lies") and "you are serving your own father" (instead of the more logical translation, "you are serving your own lord") and "If God were your father, you would follow me" (instead of the more logical translation, If God were your lord, you would follow me") 

The Jewish officials Jesus spoke to were born thousands of years after Abraham, so Abraham could not have been their father. Secondly, having Abraham as a distant ancestor does not necessarily set up a relationship of servitude. One certainly may worship an ancestor and serve an ancestor, but then this relationship would then become one of servant/lord - as Jesus discusses.

In some of the other Gospels, to clarify that Jesus was not describing a father of the physical world, the word πατήρ (patēr) was preceded by the word οὐράνιος (ouranios), which refers to the spiritual realm - often translated as "heaven" - or "heavenly."

This phrase has often been translated as "Father in heaven," or "heavenly Father," which would denote God is not to be compared with a father of physical bodies - but rather, the Creator from the spiritual realm.

An example of this:
"For if you forgive other people when they sin against you, your Father in heaven will also forgive you." (Matt. 6:14)
Which could be more appropriately translated to:
"For if you forgive other people when they sin against you, your Lord in heaven will also forgive you." (Matt. 6:14)
Or even more accurately - as strictly speaking, the "heavens" are in the physical sky:
"For if you forgive other people when they sin against you, your Lord in the spiritual realm will also forgive you." (Matt. 6:14)
These translations to "Lord" also more accurately reflect the voluntary nature of the relationship between a devoted person and God. Addressing one as "Father" indicates an official, irrevocable relationship without much choice in the matter. "Lord" invokes the position of voluntary devotion. And since God does not force anyone to worship Him or love Him, "Lord" is the most appropriate terminology, when referring to the Person Jesus is asking us to love.

This translation is also confirmed as we see the word πατήρ (patēr) used intimately in Jesus' prayers to the Supreme Person. In such prayers, to greet the One Jesus is dedicated to and loves as "Father" would be akin to one's family greeting a beloved family member as "Judge" or "Doctor." These are formal greetings, not appropriate for the intimate nature of Jesus' relationship with God. Thus, the more appropriate translation for what has been translated to:
“Father, I thank You that You have heard me." (John 11:41)
would be more appropriately translated to:
“Lord, I thank You that You have heard me." (John 11:41)
The bottom line is that Jesus and the writers of the Gospel utilized the word πατήρ (patēr) within two general contexts - one as God the Creator of everything; and the other, more intimately, as someone we can dedicate our lives to - our Lord.