Sin.
God is the author of life. He is activly engaged both physicly and spiritualy with each newly conceived child. SeePsalm 139:13-18.
Johny was always uneasy in stressful social situations and was solicious to make a good impression.
This is one of the many Messianic Psalms. Verse 11 is quoted by Satan during the temtation of Jesus in the wilderness as refering to Messiah. The key to the entire Psalm is found in verses 14 +`15. These verses along with Psalm 22:24 are the Father's response to the cry of Christ on the cross in Mt.27:46/ Ps.22:1. The verses you asked about Ps.91:1-2 when understood as coming propheticly from the mouth of Jesus Christ come clearly into focus. In addition to the primary prophetic meaning this is the experiance and promise for every child of God who is in Christ.
An individual is said to be perspicacious when they posess a keen and perceptive mind, especialy related to grasping new concepts and challenging ideas.