Never say you are losing time by going to [the Theological College]

“If theological education will increase your power for Christ, is it not your duty to gain that added power? . . . Never say you are losing time by going to school. You are saving time, buying it up for the future and storing it away. Time used in storing power is not lost.” A. T. Robertson, quoted in the Going Deeper with the New TestamentGreek, p8

Every sermon is a "salvation sermon"

Preaching is a means of grace to assist the saints to persevere. Perseverance is necessary for final salvation. Therefore, every sermon is a "salvation sermon"—not just because of its aim to convert sinners, but also in its aim to preserve the holy affections of the saints and so enable them to confirm their calling and election and be saved.
  -- p81, The Supremacy of God in Preaching by John Piper