Following God's Pattern

Rav Saul wrote, "I did not shrink from declaring to you 'the whole counsel of God.'" Why would any spiritual leader "shrink from" declaring to his flock "the whole" of God's prophetic output? This week's parasha commands us to "see to it you build according to the pattern." The whole pattern. How do we get it, and what traps can we avoid that would leave us with only part of it?