The seeking of Mt 6.33, of God’s kingdom and righteousness, is no half-hearted search, like a husband looking unsuccessfully for his socks only to appeal quickly to his wife for help. It engages the entire being, to “pursue” (NET) or “strive” (NRSV), exactly as love for God should be with the whole mind, heart, soul, and strength. Less than this is not an effort worthy of God.
Warming a pew for a few minutes on a Sunday morning (or even three times a week) is not the equivalent to this seeking, either. Ritualistic believers who think these minimal requirements will get them under the wire will be spewed out from the Lord’s mouth come judgment day.
Let no one deceive himself. Make no mistake about it.
The Lord Jesus wants disciples of his, followers in his footsteps to carry the cross, not adherents to a religion, nor believers in rote and ritual. The distinction is well made by use of the word “seek.”