Planets in houses · Kendra
Guru in the 1st house
Jupiter · Tanu Bhava
Guru is the karaka (significator) of wisdom, children, wealth and good fortune. The 1st house, called Tanu Bhava, shows self, body and personality. When Guru sits here, these matters take on its colour.
A benefic in the Lagna is a blessing: it gives a pleasant nature, good health and a likeable personality, and protects the whole chart.
The 1st house is a kendra (angular house), a pillar of the chart, so a graha here shows its results openly and strongly.
Guru gains directional strength (Dig Bala) in the 1st house, which noticeably strengthens it here.
Guru gives its best results here when it is exalted in Karka, in its own sign (Dhanu and Meena) or in a friendly sign, and when it is not combust.
Results are weaker if Guru is debilitated in Makara, combust, or afflicted by malefics.
In transit (gochar)
When Guru transits the 1st house counted from your Moon sign, the period traditionally needs more care.
A single placement is never read alone: sign, aspects, conjunctions, dasha and the whole chart change the outcome.