Now the LORD had said unto Abram, “Get thee out of thy country, and from thy kindred, and from thy father’s house, unto a land that I will shew thee: And.. I will bless thee, and make thy name great; and thou shalt be a blessing: And I will bless them that bless thee, and curse him that curseth thee…” (Gen 12:1-3, KJV)
The call of God contains both grace and truth. Truth is the separating instrument. “Get thee out.” Grace is the promise. “I will bless and make a blessing.” Man often grasps at the grace, the “I will bless” of God, and fails to comply with the demand thereof – “Get thee out.” Now this does not only apply in the matter of our salvation in its first steps, but it comes in new revelations and calls at different times in the Christian life. ~ T. Austin-Sparks 
The call of God on our lives demands change. When He calls us, he calls us out. First there is the initial call to come out from the world system and its ways among its people. When His Spirit comes into us, we quickly find that we no longer want to do the things that we once allowed. We no longer enjoy the things we once found entertaining or laughed at things we once thought were funny. We have changed, not because we have rigidly adopted a new set of religious laws to keep, but because we have found ourselves immersed in His love for us, God’s ways are what we long for.
Many of us at this point, like Abram, leave our country (our nationalism) and its ways and our worldly families (and their desires) behind as we seek that kingdom which has foundations whose Builder and Maker is God, the kingdom of heaven. But also like Abram’s father, Terah, we often settle for a habitation that falls short of what God has in mind for us–a land called Christendom. As Abram did, we head out with Terah, our old man (our old human nature), and find a place where it will be appeased as we try to please God. We get sucked into the religious ways of man which are less demanding than the ways of God. Just how long we abide in the ways of Christendom varies. Many of us go from one religious camp to another seeking the truth of our original call, but always something is just not quite right, so we move on, hoping the next church or fellowship will be the right one. Even when Abraham entered Canaan he looked for the city of God, but never found it because he was a pilgrim and sojourner in a strange land.
Therefore sprang there even of one [Abraham], and him as good as dead, so many as the stars of the sky in multitude, and as the sand which is by the sea shore innumerable. These all died in faith, not having received the promises, but having seen them afar off, and were persuaded of them, and embraced them, and confessed that they were strangers and pilgrims on the earth. For they that say such things declare plainly that they seek a country. And truly, if they had been mindful of that country from whence they came out, they might have had opportunity to have returned. But now they desire a better country, that is, an heavenly: wherefore God is not ashamed to be called their God: for he hath prepared for them a city. (Heb 11:12-16, KJV)
For us who refuse to settle for a worldly counterfeit, the call from God will continue to be “get thee out,” and “keep seeking my face.” We would like to find a place and a family here on earth we could settle down and be in a comfortable fellowship with, but He puts a desire in us to find a heavenly abode with a heavenly people and not settle for anything less.
Many of us want to be blessed by God and be a blessing to those around us, but the promise was clear–we must first get out of our former comfort zones. We must leave those who have settled there and seek not only God’s grace, but God’s truth in our lives as well. In John’s gospel we read:
For from his [Christ’s] fullness we have all received, grace upon grace. For the law was given through Moses; grace and truth came through Jesus Christ. (John 1:15-17, ESV2011)
Grace upon grace, yes, we all want the grace of God to abound in our lives and to not live under the law, but both grace and Truth came through Jesus Christ. God desires not only to bless us, but He also wants us to live lives true to Him. He desires truth to dwell in our inward parts (Psalm 51:6) — in our hearts. Both grace and Truth are ours only as we live our lives in Christ and not in our own fleshly ways or the fleshly desires of those who want to pull us down to their level. T.A. Sparks continues:
The call of God to some fuller and higher acceptance of truth and ministry; of testimony and witness; of surrender and experience, will undoubtedly come by one or another of the Divine forms of visitation to such as the Lord wishes to lead in grace. This will be timed, definite, and challenging. A messenger may come as out from nowhere; the nowhere of [no] reputation, recognition, worldly fame or honour. He will deliver a message, only staying long enough to leave its essential implications with those who hear. Then, having passed on, things can never be the same for them again.
The “call” has sounded. The crisis has been precipitated. The issue is between the life which has been with its limitations known or unrecognised, and that which God offers. But, as usually is the case, this truth is going to call for a “getting out.” Getting out, it may be, [out] of a certain popularity, a comparative easy going. There may be a risking of reputation, a loss of prestige, a disfavour among men, a being labelled “singular,” “peculiar,” “extreme,” “unsafe.” It may mean a head-on impact of all the prejudice, tradition, and disfavour of the religious world. It may involve exclusion, ostracism, and suspicion. These are the accompaniments of all calls of God to advance with Him beyond accepted standards. This is the cost of path-finding for souls. This is the price to be paid for the higher serviceableness to God and men…
“These shall war against the Lamb, and the Lamb shall overcome them, for he is Lord of lords, and King of kings; and they also shall overcome that are with him, called and chosen and faithful.” (Revelation 17:14)
Oh, beloved of God, let us go all the way and whatever it may involve – it will never be in advance of the apostolic suffering – aspire to be of “the called, chosen, and faithful.” 
~ A Special thanks to Susanne Schuberth for bringing this article by T.A. Sparks to my attention ~